diff --git a/README.md b/README.md
index b5b0059..ace205d 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,345 @@
 # horde/githubapiclient
 
-A horde/http based client for the Github REST API.
+A horde/http based client for the GitHub REST API v3.
 
-## Usage
+## Installation
 
-See bin/demo-client.php for basic usage
\ No newline at end of file
+```bash
+composer require horde/githubapiclient
+```
+
+**Upgrading?** See the [Migration Guide](doc/MIGRATION.md) for upgrading from earlier versions.
+
+## Quick Start
+
+```php
+use Horde\GithubApiClient\GithubApiClient;
+use Horde\GithubApiClient\GithubApiConfig;
+use Horde\GithubApiClient\GithubRepository;
+use Horde\Http\Client;
+
+// Create configuration
+$config = new GithubApiConfig(accessToken: 'your-github-token');
+
+// Create HTTP client (PSR-18 compatible)
+$httpClient = new Client();
+$requestFactory = new \Horde\Http\RequestFactory();
+$streamFactory = new \Horde\Http\StreamFactory();
+
+// Create API client
+$client = new GithubApiClient($httpClient, $requestFactory, $config, $streamFactory);
+
+// Use the client
+$repo = new GithubRepository(owner: 'horde', name: 'components');
+$pullRequests = $client->listPullRequests($repo);
+```
+
+## Features
+
+### Repository Management
+- List repositories in an organization
+- Get repository details
+
+### Pull Requests
+- Create new pull requests
+- List pull requests with filters (base branch, head ref, state)
+- Get a single pull request with complete details
+- Update pull request (title, body, base branch, state)
+- Merge pull requests (merge, squash, or rebase)
+- Close pull requests
+- Reopen closed pull requests
+
+### Comments
+- List all comments on a pull request
+- Create a comment on a pull request
+- Update existing comments
+- Delete comments
+
+### Reviews
+- List all reviews on a pull request
+- Request reviewers (users and teams)
+- Check review states (APPROVED, CHANGES_REQUESTED, COMMENTED, DISMISSED)
+
+### Status Checks
+- Get combined commit status
+- List GitHub Actions check runs
+- Monitor CI/CD pipeline status
+
+### Labels
+- List labels on issues/pull requests
+- Add labels to issues/pull requests
+- Set (replace) all labels on issues/pull requests
+- Remove labels from issues/pull requests
+
+### Rate Limiting
+- Check current rate limit status
+- Inspect OAuth token scopes
+
+## Detailed Usage
+
+### Working with Pull Requests
+
+#### List Pull Requests
+
+```php
+$repo = new GithubRepository(owner: 'horde', name: 'components');
+
+// List all open pull requests
+$pullRequests = $client->listPullRequests($repo);
+
+// Filter by base branch
+$pullRequests = $client->listPullRequests($repo, baseBranch: 'main');
+
+// Filter by head ref
+$pullRequests = $client->listPullRequests($repo, headRef: 'feature-branch');
+
+foreach ($pullRequests as $pr) {
+    echo "PR #{$pr->number}: {$pr->title}\n";
+}
+```
+
+#### Get Pull Request Details
+
+```php
+$pr = $client->getPullRequest($repo, number: 123);
+
+echo "Title: {$pr->title}\n";
+echo "State: {$pr->state}\n";
+echo "Mergeable: " . ($pr->mergeable ? 'Yes' : 'No') . "\n";
+echo "Draft: " . ($pr->draft ? 'Yes' : 'No') . "\n";
+```
+
+#### Create Pull Request
+
+```php
+use Horde\GithubApiClient\CreatePullRequestParams;
+
+// Create a regular pull request
+$params = new CreatePullRequestParams(
+    title: 'Add new feature',
+    head: 'feature-branch',
+    base: 'main',
+    body: 'This PR adds a new feature\n\nCloses #123'
+);
+$newPr = $client->createPullRequest($repo, $params);
+
+// Create a draft pull request
+$draftParams = new CreatePullRequestParams(
+    title: 'Work in progress',
+    head: 'wip-branch',
+    base: 'develop',
+    body: 'This is still being worked on',
+    draft: true
+);
+$draftPr = $client->createPullRequest($repo, $draftParams);
+
+// Create PR from a fork
+$forkParams = new CreatePullRequestParams(
+    title: 'Fix from fork',
+    head: 'username:feature-branch',  // Format: username:branch
+    base: 'main'
+);
+$forkPr = $client->createPullRequest($repo, $forkParams);
+```
+
+#### Update Pull Request
+
+```php
+use Horde\GithubApiClient\PullRequestUpdate;
+
+// Update title and body
+$update = new PullRequestUpdate(
+    title: 'New PR Title',
+    body: 'Updated description'
+);
+$updatedPr = $client->updatePullRequest($repo, 123, $update);
+
+// Change base branch
+$update = new PullRequestUpdate(base: 'develop');
+$updatedPr = $client->updatePullRequest($repo, 123, $update);
+
+// Close a pull request
+$closedPr = $client->closePullRequest($repo, 123);
+
+// Reopen a closed pull request
+$reopenedPr = $client->reopenPullRequest($repo, 123);
+```
+
+#### Merge Pull Request
+
+```php
+use Horde\GithubApiClient\MergePullRequestParams;
+
+// Simple merge with defaults
+$params = new MergePullRequestParams();
+$result = $client->mergePullRequest($repo, 123, $params);
+
+if ($result->merged) {
+    echo "Merged successfully: {$result->sha}\n";
+}
+
+// Squash merge with custom commit message
+$params = new MergePullRequestParams(
+    commitTitle: 'feat: add new feature',
+    commitMessage: 'This PR implements feature X\n\nCloses #123',
+    mergeMethod: 'squash'
+);
+$result = $client->mergePullRequest($repo, 123, $params);
+
+// Rebase merge
+$params = new MergePullRequestParams(mergeMethod: 'rebase');
+$result = $client->mergePullRequest($repo, 123, $params);
+
+// Safe merge with SHA check
+$params = new MergePullRequestParams(
+    sha: 'abc123def456',  // Only merge if head SHA matches
+    mergeMethod: 'merge'
+);
+$result = $client->mergePullRequest($repo, 123, $params);
+```
+
+### Working with Comments
+
+```php
+// List comments
+$comments = $client->listPullRequestComments($repo, 123);
+foreach ($comments as $comment) {
+    echo "{$comment->author->login}: {$comment->body}\n";
+}
+
+// Create a comment
+$comment = $client->createPullRequestComment($repo, 123, 'Looks good to me!');
+echo "Created comment: {$comment->htmlUrl}\n";
+
+// Update a comment
+$updatedComment = $client->updateComment($repo, $comment->id, 'Updated comment text');
+
+// Delete a comment
+$client->deleteComment($repo, $comment->id);
+```
+
+### Working with Reviews
+
+```php
+// List reviews
+$reviews = $client->listPullRequestReviews($repo, 123);
+foreach ($reviews as $review) {
+    echo "{$review->user->login}: {$review->state}\n";
+}
+
+// Request reviewers
+$updatedPr = $client->requestReviewers(
+    $repo,
+    123,
+    reviewers: ['username1', 'username2'],
+    teamReviewers: ['team-slug']
+);
+```
+
+### Working with Status Checks
+
+```php
+// Get combined status for a commit or branch
+$status = $client->getCombinedStatus($repo, 'main');
+echo "Overall status: {$status->state}\n";
+echo "Total checks: {$status->totalCount}\n";
+
+foreach ($status->statuses as $check) {
+    echo "{$check->context}: {$check->state}\n";
+}
+
+// List check runs (GitHub Actions)
+$checkRuns = $client->listCheckRuns($repo, 'feature-branch');
+foreach ($checkRuns as $run) {
+    echo "{$run->name}: {$run->status}/{$run->conclusion}\n";
+}
+```
+
+### Working with Labels
+
+```php
+// List labels
+$labels = $client->listIssueLabels($repo, 123);
+foreach ($labels as $label) {
+    echo "{$label->name} (#{$label->color})\n";
+}
+
+// Add labels
+$labels = $client->addLabels($repo, 123, ['bug', 'priority-high']);
+
+// Set labels (replaces all existing labels)
+$labels = $client->setLabels($repo, 123, ['bug', 'in-progress']);
+
+// Remove a label
+$client->removeLabel($repo, 123, 'wontfix');
+```
+
+### Rate Limiting and Token Information
+
+```php
+// Check rate limit
+$rateLimit = $client->getRateLimit();
+echo "Remaining: {$rateLimit->remaining}/{$rateLimit->limit}\n";
+echo "Resets at: {$rateLimit->reset}\n";
+
+// Check token scopes
+$scopes = $client->getTokenScopes();
+if ($scopes->hasScope('repo')) {
+    echo "Token has repo access\n";
+}
+```
+
+## Architecture
+
+This library follows a Request Factory pattern:
+
+- **Value Objects**: Immutable data classes (`GithubPullRequest`, `GithubComment`, etc.)
+- **Factories**: Create value objects from API responses
+- **Request Factories**: Build PSR-7 HTTP requests for each API endpoint
+- **Collections**: Typed collections implementing `Iterator` and `Countable`
+- **DTOs**: Data Transfer Objects for complex request parameters
+
+All classes use PHP 8.2+ features including:
+- Named parameters
+- Readonly properties
+- Strict types
+- Constructor property promotion
+
+## Testing
+
+```bash
+# Run unit tests
+vendor/bin/phpunit
+
+# Run with coverage
+vendor/bin/phpunit --coverage-html coverage/
+```
+
+## Requirements
+
+- PHP 8.2 or higher
+- PSR-18 HTTP Client implementation
+- PSR-7 HTTP Message implementation
+- PSR-17 HTTP Factories implementation
+
+## License
+
+See the enclosed file LICENSE for license information (LGPL 2.1).
+
+## Contributing
+
+This package follows PER-1 coding standards with strict type declarations.
+
+All commits should follow the Conventional Commits specification:
+- `feat:` - New features
+- `fix:` - Bug fixes
+- `docs:` - Documentation changes
+- `test:` - Test additions or modifications
+- `refactor:` - Code refactoring
+- `chore:` - Maintenance tasks
+
+## Additional Documentation
+
+- [API Reference](doc/API.md) - Complete API documentation for all classes and methods
+- [Migration Guide](doc/MIGRATION.md) - Guide for upgrading from earlier versions
+- `bin/demo-client.php` - Working examples of all features
\ No newline at end of file
diff --git a/bin/demo-client.php b/bin/demo-client.php
index b187ca5..0c9bc75 100755
--- a/bin/demo-client.php
+++ b/bin/demo-client.php
@@ -21,6 +21,7 @@
 use Horde\Http\ResponseFactory;
 use Psr\Http\Client\ClientInterface;
 use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\StreamFactoryInterface;
 
 // Bootstrap the injector
 $strGithubApiToken = (string) getenv('GITHUB_TOKEN');
@@ -32,10 +33,167 @@
 // Setup a curl client. This is a demo, don't get too involved
 $injector->setInstance(ClientInterface::class, new CurlClient(new ResponseFactory(), new StreamFactory(), new Options()));
 $injector->setInstance(RequestFactoryInterface::class, new RequestFactory());
+$injector->setInstance(StreamFactoryInterface::class, new StreamFactory());
 $injector->setInstance(GithubApiConfig::class, new GithubApiConfig(accessToken: $strGithubApiToken));
 $client = $injector->get(GithubApiClient::class);
+
+echo "=== GitHub API Client Demo ===\n\n";
+
+// Example 1: List repositories in organization
+echo "1. Listing repositories in Horde organization:\n";
 $repos = $client->listRepositoriesInOrganization(new GithubOrganizationId('horde'));
+$count = 0;
 foreach ($repos as $repo) {
-    echo $repo->getFullName() . "\n";
+    echo "  - {$repo->getFullName()}\n";
+    if (++$count >= 5) {
+        echo "  ... (showing first 5)\n";
+        break;
+    }
+}
+echo "\n";
+
+// Example 2: Check rate limit
+echo "2. Checking rate limit:\n";
+$rateLimit = $client->getRateLimit();
+echo "  Remaining: {$rateLimit->remaining}/{$rateLimit->limit}\n";
+echo "  Resets at: {$rateLimit->reset}\n\n";
+
+// Example 3: Check token scopes
+echo "3. Checking token scopes:\n";
+$scopes = $client->getTokenScopes();
+echo "  Has repo scope: " . ($scopes->hasScope('repo') ? 'Yes' : 'No') . "\n";
+echo "  Has workflow scope: " . ($scopes->hasScope('workflow') ? 'Yes' : 'No') . "\n\n";
+
+// Example 4: List pull requests (if DEMO_REPO is set)
+$demoRepo = getenv('DEMO_REPO');
+if ($demoRepo && strpos($demoRepo, '/') !== false) {
+    [$owner, $name] = explode('/', $demoRepo, 2);
+    $repo = new GithubRepository(owner: $owner, name: $name);
+
+    echo "4. Listing pull requests for {$demoRepo}:\n";
+    $pullRequests = $client->listPullRequests($repo, state: 'open');
+    $prCount = 0;
+    foreach ($pullRequests as $pr) {
+        echo "  PR #{$pr->number}: {$pr->title}\n";
+        echo "    State: {$pr->state}, Draft: " . ($pr->draft ? 'Yes' : 'No') . "\n";
+
+        if (++$prCount >= 3) {
+            echo "  ... (showing first 3)\n";
+            break;
+        }
+    }
+    echo "\n";
+
+    // Example 5: Get detailed PR info for first PR
+    if ($prCount > 0) {
+        $firstPr = $pullRequests->toArray()[0];
+        echo "5. Getting detailed info for PR #{$firstPr->number}:\n";
+        $detailedPr = $client->getPullRequest($repo, $firstPr->number);
+        echo "  Author: {$detailedPr->author->login}\n";
+        echo "  Created: {$detailedPr->createdAt}\n";
+        echo "  Mergeable: " . ($detailedPr->mergeable ? 'Yes' : 'No') . "\n";
+        echo "  Labels: " . count($detailedPr->labels) . "\n";
+        echo "  Reviewers: " . count($detailedPr->requestedReviewers) . "\n\n";
+
+        // Example 6: List comments
+        echo "6. Listing comments on PR #{$firstPr->number}:\n";
+        $comments = $client->listPullRequestComments($repo, $firstPr->number);
+        echo "  Total comments: " . count($comments) . "\n";
+        foreach ($comments as $comment) {
+            echo "  - {$comment->author->login}: " . substr($comment->body, 0, 50) . "...\n";
+            if (++$commentCount >= 3) {
+                echo "  ... (showing first 3)\n";
+                break;
+            }
+        }
+        echo "\n";
+
+        // Example 7: List reviews
+        echo "7. Listing reviews on PR #{$firstPr->number}:\n";
+        $reviews = $client->listPullRequestReviews($repo, $firstPr->number);
+        echo "  Total reviews: " . count($reviews) . "\n";
+        foreach ($reviews as $review) {
+            echo "  - {$review->user->login}: {$review->state}\n";
+        }
+        echo "\n";
+
+        // Example 8: Check CI/CD status
+        echo "8. Checking CI/CD status for PR #{$firstPr->number}:\n";
+        $status = $client->getCombinedStatus($repo, $detailedPr->headSha);
+        echo "  Overall status: {$status->state}\n";
+        echo "  Total checks: {$status->totalCount}\n";
+
+        $checkRuns = $client->listCheckRuns($repo, $detailedPr->headSha);
+        echo "  Check runs: " . count($checkRuns) . "\n";
+        foreach ($checkRuns as $run) {
+            echo "  - {$run->name}: {$run->status}";
+            if ($run->conclusion) {
+                echo " ({$run->conclusion})";
+            }
+            echo "\n";
+        }
+        echo "\n";
+    }
+} else {
+    echo "4-8. Skipped (set DEMO_REPO=owner/repo to see PR examples)\n\n";
 }
-// List Releases of a repo
+
+// Example 9: Create a pull request (if CREATE_PR_DEMO=1 is set)
+if (getenv('CREATE_PR_DEMO') === '1' && $demoRepo && strpos($demoRepo, '/') !== false) {
+    [$owner, $name] = explode('/', $demoRepo, 2);
+    $repo = new GithubRepository(owner: $owner, name: $name);
+
+    echo "9. Creating a demo pull request:\n";
+
+    $headBranch = getenv('PR_HEAD_BRANCH') ?: 'demo-branch';
+    $baseBranch = getenv('PR_BASE_BRANCH') ?: 'main';
+
+    try {
+        $createParams = new CreatePullRequestParams(
+            title: 'Demo PR - API Client Test',
+            head: $headBranch,
+            base: $baseBranch,
+            body: "This is a demo pull request created by the GitHub API Client.\n\n" .
+                  "Created at: " . date('Y-m-d H:i:s') . "\n" .
+                  "This PR can be safely closed.",
+            draft: (getenv('PR_DRAFT') === '1'),
+            maintainerCanModify: true
+        );
+
+        $newPr = $client->createPullRequest($repo, $createParams);
+        echo "  ✓ Created PR #{$newPr->number}: {$newPr->title}\n";
+        echo "  URL: {$newPr->htmlUrl}\n";
+        echo "  State: {$newPr->state}\n";
+        echo "  Draft: " . ($newPr->draft ? 'Yes' : 'No') . "\n";
+
+        // Example 10: Demonstrate reopen functionality by closing and reopening
+        if (getenv('DEMO_REOPEN') === '1') {
+            echo "\n10. Demonstrating close and reopen:\n";
+
+            // Close the PR
+            $closedPr = $client->closePullRequest($repo, $newPr->number);
+            echo "  ✓ Closed PR #{$closedPr->number}, state: {$closedPr->state}\n";
+
+            sleep(1); // Brief pause for API rate limiting
+
+            // Reopen the PR
+            $reopenedPr = $client->reopenPullRequest($repo, $newPr->number);
+            echo "  ✓ Reopened PR #{$reopenedPr->number}, state: {$reopenedPr->state}\n";
+        }
+
+    } catch (\Exception $e) {
+        echo "  ✗ Error: {$e->getMessage()}\n";
+        echo "  Note: Make sure the head branch exists and differs from base branch\n";
+    }
+    echo "\n";
+}
+
+echo "=== Demo Complete ===\n";
+echo "\nTo see PR-related examples, export DEMO_REPO=owner/repo\n";
+echo "Example: export DEMO_REPO=horde/components\n";
+echo "\nTo test PR creation, also set:\n";
+echo "  CREATE_PR_DEMO=1        Enable PR creation demo\n";
+echo "  PR_HEAD_BRANCH=branch   Source branch (default: demo-branch)\n";
+echo "  PR_BASE_BRANCH=branch   Target branch (default: main)\n";
+echo "  PR_DRAFT=1              Create as draft PR\n";
+echo "  DEMO_REOPEN=1           Demonstrate close/reopen functionality\n";
diff --git a/create-pr.php b/create-pr.php
new file mode 100755
index 0000000..8051c59
--- /dev/null
+++ b/create-pr.php
@@ -0,0 +1,227 @@
+#!/usr/bin/env php
+<?php
+
+/**
+ * Script to create a pull request for the enhanced-pull-request-api feature
+ *
+ * Usage:
+ *   export GITHUB_TOKEN=your_token
+ *   php create-pr.php
+ */
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+require_once __DIR__ . '/vendor/autoload.php';
+
+use Horde\Injector\Injector;
+use Horde\Injector\TopLevel;
+use Horde\Http\Client\Options;
+use Horde\Http\Client\Curl as CurlClient;
+use Horde\Http\StreamFactory;
+use Horde\Http\RequestFactory;
+use Horde\Http\ResponseFactory;
+use Psr\Http\Client\ClientInterface;
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+
+// Check for GitHub token
+$githubToken = (string) getenv('GITHUB_TOKEN');
+if (empty($githubToken)) {
+    echo "Error: GITHUB_TOKEN environment variable is not set.\n";
+    echo "Usage: export GITHUB_TOKEN=your_token && php create-pr.php\n";
+    exit(1);
+}
+
+// Setup dependency injection
+$injector = new Injector(new TopLevel());
+$injector->setInstance(ClientInterface::class, new CurlClient(new ResponseFactory(), new StreamFactory(), new Options()));
+$injector->setInstance(RequestFactoryInterface::class, new RequestFactory());
+$injector->setInstance(StreamFactoryInterface::class, new StreamFactory());
+$injector->setInstance(GithubApiConfig::class, new GithubApiConfig(accessToken: $githubToken));
+
+$client = $injector->get(GithubApiClient::class);
+
+// Repository details
+$repo = GithubRepository::fromFullName('horde/githubapiclient');
+
+// PR details
+$title = 'feat: add comprehensive pull request management API';
+
+$body = <<<'MARKDOWN'
+## Summary
+
+This PR adds comprehensive pull request management capabilities to the GitHub API Client, transforming it from a basic client into a full-featured PR automation tool.
+
+## Features Added
+
+### Pull Request Operations
+- ✅ Create pull requests (including draft PRs and from forks)
+- ✅ List pull requests with filters (base branch, head ref, state)
+- ✅ Get detailed pull request information
+- ✅ Update pull requests (title, body, base branch, state)
+- ✅ Merge pull requests (merge, squash, rebase methods)
+- ✅ Close pull requests
+- ✅ Reopen closed pull requests
+
+### Comment Management
+- ✅ List all comments on pull requests
+- ✅ Create comments
+- ✅ Update comments
+- ✅ Delete comments
+
+### Review Management
+- ✅ List pull request reviews
+- ✅ Request reviewers (users and teams)
+- ✅ Support for all review states (APPROVED, CHANGES_REQUESTED, COMMENTED, DISMISSED)
+
+### Status Checks & CI/CD
+- ✅ Get combined commit status
+- ✅ List GitHub Actions check runs
+- ✅ Monitor pipeline status and conclusions
+
+### Label Management
+- ✅ List labels on issues/pull requests
+- ✅ Add labels
+- ✅ Set (replace) all labels
+- ✅ Remove labels
+
+## Technical Implementation
+
+### Architecture
+- **Request Factory Pattern**: Each API endpoint has a dedicated request factory
+- **Value Objects**: Immutable domain objects with static factory methods
+- **DTOs**: Clean data transfer objects for complex parameters
+- **Typed Collections**: All collections implement `Iterator` and `Countable`
+- **PHP 8.2+ Features**: Named parameters, readonly properties, strict types
+- **PSR Compliant**: PSR-7, PSR-17, PSR-18
+
+### Code Quality
+- **71 unit tests** with **249 assertions** - all passing ✅
+- **52 files changed**: 5,217 insertions, 7 deletions
+- **PER-1 coding standards** throughout
+- **Conventional Commits** for all commits
+
+## Documentation
+
+### Added Documentation Files
+- **README.md**: Comprehensive usage guide with examples for all features
+- **doc/API.md**: Complete API reference (574 lines)
+- **doc/MIGRATION.md**: Upgrade guide with backwards compatibility notes (305 lines)
+- **bin/demo-client.php**: Enhanced with 10 working examples
+
+## Breaking Changes
+
+**None** - This is a backwards-compatible addition. Existing code continues to work unchanged.
+
+**Optional Enhancement**: Add `StreamFactoryInterface` parameter to constructor to enable write operations:
+```php
+$client = new GithubApiClient($httpClient, $requestFactory, $config, $streamFactory);
+```
+
+## Example Usage
+
+### Create a Pull Request
+```php
+use Horde\GithubApiClient\CreatePullRequestParams;
+
+$params = new CreatePullRequestParams(
+    title: 'Add new feature',
+    head: 'feature-branch',
+    base: 'main',
+    body: 'This PR adds...'
+);
+$pr = $client->createPullRequest($repo, $params);
+```
+
+### Merge a Pull Request
+```php
+use Horde\GithubApiClient\MergePullRequestParams;
+
+$params = new MergePullRequestParams(
+    commitTitle: 'feat: add feature',
+    mergeMethod: 'squash'
+);
+$result = $client->mergePullRequest($repo, 123, $params);
+```
+
+### Manage Comments and Reviews
+```php
+// Add a comment
+$comment = $client->createPullRequestComment($repo, 123, 'LGTM!');
+
+// Request reviewers
+$client->requestReviewers($repo, 123, ['reviewer1', 'reviewer2']);
+
+// Check CI status
+$status = $client->getCombinedStatus($repo, 'main');
+echo "Status: {$status->state}\n";
+```
+
+## Test Plan
+
+- [x] All 71 unit tests passing
+- [x] Demo client tested with real GitHub API
+- [x] Documentation reviewed and examples verified
+- [x] Backwards compatibility verified
+- [x] Code follows PER-1 and Conventional Commits standards
+
+## Commits
+
+This PR includes 10 well-structured commits:
+1. Enhanced pull request API with user and label support
+2. Pull request update capability
+3. Pull request comment management
+4. Pull request review management
+5. Commit status and check runs support
+6. Label management support
+7. Pull request merge and close support
+8. Comprehensive documentation and examples
+9. Create and reopen pull request functionality
+10. Factory method and constructor documentation improvements
+
+## Checklist
+
+- [x] Code follows project coding standards (PER-1)
+- [x] Unit tests added and passing (71 tests, 249 assertions)
+- [x] Documentation updated (README, API reference, migration guide)
+- [x] Backwards compatible (existing code unaffected)
+- [x] Conventional Commits used for all commits
+- [x] Demo client includes working examples
+- [x] No breaking changes introduced
+
+## Related Issues
+
+Closes #[issue number if applicable]
+MARKDOWN;
+
+echo "Creating pull request...\n";
+echo "Repository: horde/githubapiclient\n";
+echo "Head: feat/enhanced-pull-request-api\n";
+echo "Base: FRAMEWORK_6_0\n\n";
+
+try {
+    $params = new CreatePullRequestParams(
+        title: $title,
+        head: 'feat/enhanced-pull-request-api',
+        base: 'FRAMEWORK_6_0',
+        body: $body,
+        draft: false,
+        maintainerCanModify: true
+    );
+
+    $pr = $client->createPullRequest($repo, $params);
+
+    echo "✅ Pull request created successfully!\n\n";
+    echo "PR #{$pr->number}: {$pr->title}\n";
+    echo "URL: {$pr->htmlUrl}\n";
+    echo "State: {$pr->state}\n";
+    echo "Author: {$pr->author->login}\n";
+    echo "\nYou can view the PR at: {$pr->htmlUrl}\n";
+
+} catch (\Exception $e) {
+    echo "❌ Error creating pull request:\n";
+    echo $e->getMessage() . "\n";
+    exit(1);
+}
diff --git a/doc/API.md b/doc/API.md
new file mode 100644
index 0000000..b062239
--- /dev/null
+++ b/doc/API.md
@@ -0,0 +1,574 @@
+# GitHub API Client - API Reference
+
+## Table of Contents
+
+- [GithubApiClient](#githubapiclient)
+- [Configuration](#configuration)
+- [Value Objects](#value-objects)
+- [Collections](#collections)
+- [DTOs](#dtos)
+
+## GithubApiClient
+
+Main client class for interacting with the GitHub API.
+
+### Constructor
+
+```php
+public function __construct(
+    ClientInterface $httpClient,
+    RequestFactoryInterface $requestFactory,
+    GithubApiConfig $config,
+    ?StreamFactoryInterface $streamFactory = null
+)
+```
+
+**Parameters:**
+- `$httpClient` - PSR-18 HTTP client
+- `$requestFactory` - PSR-17 request factory
+- `$config` - GitHub API configuration (contains access token)
+- `$streamFactory` - PSR-17 stream factory (required for POST/PUT/PATCH operations)
+
+### Repository Methods
+
+#### listRepositoriesInOrganization()
+
+List all repositories in an organization.
+
+```php
+public function listRepositoriesInOrganization(
+    GithubOrganizationId $org
+): GithubRepositoryList
+```
+
+**Returns:** Collection of repositories
+
+### Pull Request Methods
+
+#### listPullRequests()
+
+List pull requests in a repository.
+
+```php
+public function listPullRequests(
+    GithubRepository $repo,
+    string $baseBranch = '',
+    string $headRef = '',
+    string $state = 'open'
+): GithubPullRequestList
+```
+
+**Parameters:**
+- `$repo` - The repository
+- `$baseBranch` - Filter by base branch (optional)
+- `$headRef` - Filter by head reference (optional)
+- `$state` - Filter by state: 'open', 'closed', 'all' (default: 'open')
+
+**Returns:** Collection of pull requests
+
+#### getPullRequest()
+
+Get a single pull request with complete details.
+
+```php
+public function getPullRequest(
+    GithubRepository $repo,
+    int $number
+): GithubPullRequest
+```
+
+**Returns:** Complete pull request details
+
+#### createPullRequest()
+
+Create a new pull request.
+
+```php
+public function createPullRequest(
+    GithubRepository $repo,
+    CreatePullRequestParams $params
+): GithubPullRequest
+```
+
+**Parameters:**
+- `$repo` - The repository
+- `$params` - Pull request creation parameters
+
+**Returns:** The created pull request
+
+#### updatePullRequest()
+
+Update a pull request's title, body, base branch, or state.
+
+```php
+public function updatePullRequest(
+    GithubRepository $repo,
+    int $number,
+    PullRequestUpdate $update
+): GithubPullRequest
+```
+
+**Returns:** Updated pull request
+
+#### reopenPullRequest()
+
+Reopen a closed pull request.
+
+```php
+public function reopenPullRequest(
+    GithubRepository $repo,
+    int $number
+): GithubPullRequest
+```
+
+**Returns:** Reopened pull request
+
+#### mergePullRequest()
+
+Merge a pull request.
+
+```php
+public function mergePullRequest(
+    GithubRepository $repo,
+    int $number,
+    MergePullRequestParams $params
+): MergeResult
+```
+
+**Parameters:**
+- `$params` - Merge configuration (method, commit message, etc.)
+
+**Returns:** Merge operation result
+
+#### closePullRequest()
+
+Close a pull request without merging.
+
+```php
+public function closePullRequest(
+    GithubRepository $repo,
+    int $number
+): GithubPullRequest
+```
+
+**Returns:** Closed pull request
+
+### Comment Methods
+
+#### listPullRequestComments()
+
+List all comments on a pull request.
+
+```php
+public function listPullRequestComments(
+    GithubRepository $repo,
+    int $number
+): GithubCommentList
+```
+
+**Returns:** Collection of comments
+
+#### createPullRequestComment()
+
+Create a comment on a pull request.
+
+```php
+public function createPullRequestComment(
+    GithubRepository $repo,
+    int $number,
+    string $body
+): GithubComment
+```
+
+**Returns:** Created comment
+
+#### updateComment()
+
+Update an existing comment.
+
+```php
+public function updateComment(
+    GithubRepository $repo,
+    int $commentId,
+    string $body
+): GithubComment
+```
+
+**Returns:** Updated comment
+
+#### deleteComment()
+
+Delete a comment.
+
+```php
+public function deleteComment(
+    GithubRepository $repo,
+    int $commentId
+): void
+```
+
+### Review Methods
+
+#### listPullRequestReviews()
+
+List all reviews on a pull request.
+
+```php
+public function listPullRequestReviews(
+    GithubRepository $repo,
+    int $number
+): GithubReviewList
+```
+
+**Returns:** Collection of reviews
+
+#### requestReviewers()
+
+Request reviewers for a pull request.
+
+```php
+public function requestReviewers(
+    GithubRepository $repo,
+    int $number,
+    array $reviewers = [],
+    array $teamReviewers = []
+): GithubPullRequest
+```
+
+**Parameters:**
+- `$reviewers` - Array of user logins
+- `$teamReviewers` - Array of team slugs
+
+**Returns:** Updated pull request with requested reviewers
+
+### Status Check Methods
+
+#### getCombinedStatus()
+
+Get combined status for a commit.
+
+```php
+public function getCombinedStatus(
+    GithubRepository $repo,
+    string $ref
+): GithubCombinedStatus
+```
+
+**Parameters:**
+- `$ref` - Commit SHA, branch name, or tag name
+
+**Returns:** Combined status with all checks
+
+#### listCheckRuns()
+
+List check runs (GitHub Actions) for a commit.
+
+```php
+public function listCheckRuns(
+    GithubRepository $repo,
+    string $ref
+): GithubCheckRunList
+```
+
+**Parameters:**
+- `$ref` - Commit SHA, branch name, or tag name
+
+**Returns:** Collection of check runs
+
+### Label Methods
+
+#### listIssueLabels()
+
+List labels on an issue or pull request.
+
+```php
+public function listIssueLabels(
+    GithubRepository $repo,
+    int $number
+): GithubLabelList
+```
+
+**Returns:** Collection of labels
+
+#### addLabels()
+
+Add labels to an issue or pull request.
+
+```php
+public function addLabels(
+    GithubRepository $repo,
+    int $number,
+    array $labels
+): GithubLabelList
+```
+
+**Parameters:**
+- `$labels` - Array of label names
+
+**Returns:** Updated list of labels
+
+#### setLabels()
+
+Set (replace) all labels on an issue or pull request.
+
+```php
+public function setLabels(
+    GithubRepository $repo,
+    int $number,
+    array $labels
+): GithubLabelList
+```
+
+**Parameters:**
+- `$labels` - Array of label names
+
+**Returns:** Updated list of labels
+
+#### removeLabel()
+
+Remove a label from an issue or pull request.
+
+```php
+public function removeLabel(
+    GithubRepository $repo,
+    int $number,
+    string $labelName
+): void
+```
+
+### Rate Limit Methods
+
+#### getRateLimit()
+
+Get current rate limit status.
+
+```php
+public function getRateLimit(): RateLimit
+```
+
+**Returns:** Rate limit information
+
+#### getTokenScopes()
+
+Get OAuth scopes for the current access token.
+
+```php
+public function getTokenScopes(): TokenScopes
+```
+
+**Returns:** Token scope information
+
+## Configuration
+
+### GithubApiConfig
+
+Configuration object containing API credentials.
+
+```php
+public function __construct(
+    public readonly string $accessToken
+)
+```
+
+## Value Objects
+
+### GithubPullRequest
+
+Represents a GitHub pull request.
+
+**Properties:**
+- `int $number` - Pull request number
+- `string $title` - Pull request title
+- `string $state` - State: 'open', 'closed', 'merged'
+- `string $htmlUrl` - Web URL
+- `?string $body` - Description body
+- `bool $draft` - Is draft PR
+- `bool $merged` - Is merged
+- `?string $mergedAt` - Merge timestamp
+- `string $createdAt` - Creation timestamp
+- `string $updatedAt` - Last update timestamp
+- `string $headRef` - Head branch name
+- `string $baseRef` - Base branch name
+- `string $headSha` - Head commit SHA
+- `?GithubUser $author` - PR author
+- `array<GithubLabel> $labels` - Labels
+- `array<GithubUser> $requestedReviewers` - Requested reviewers
+- `?bool $mergeable` - Can be merged
+- `?string $mergeableState` - Mergeable state
+
+### GithubComment
+
+Represents a comment on a pull request.
+
+**Properties:**
+- `int $id` - Comment ID
+- `string $body` - Comment text
+- `GithubUser $author` - Comment author
+- `string $createdAt` - Creation timestamp
+- `string $updatedAt` - Last update timestamp
+- `string $htmlUrl` - Web URL
+- `string $apiUrl` - API URL
+
+### GithubReview
+
+Represents a pull request review.
+
+**Properties:**
+- `int $id` - Review ID
+- `GithubUser $user` - Reviewer
+- `string $body` - Review comment
+- `string $state` - Review state: 'APPROVED', 'CHANGES_REQUESTED', 'COMMENTED', 'DISMISSED'
+- `string $htmlUrl` - Web URL
+- `string $submittedAt` - Submission timestamp
+- `string $commitId` - Commit SHA reviewed
+
+### GithubUser
+
+Represents a GitHub user.
+
+**Properties:**
+- `string $login` - Username
+- `int $id` - User ID
+- `string $avatarUrl` - Avatar URL
+- `string $htmlUrl` - Profile URL
+- `string $type` - User type: 'User', 'Bot', 'Organization'
+
+### GithubLabel
+
+Represents a label.
+
+**Properties:**
+- `string $name` - Label name
+- `string $color` - Hex color (without #)
+- `string $description` - Label description
+
+### GithubCommitStatus
+
+Represents a commit status check.
+
+**Properties:**
+- `string $state` - Status: 'success', 'failure', 'pending', 'error'
+- `string $context` - Check context/name
+- `string $description` - Status description
+- `string $targetUrl` - Details URL
+- `string $createdAt` - Creation timestamp
+- `string $updatedAt` - Update timestamp
+
+### GithubCombinedStatus
+
+Represents combined status of all checks.
+
+**Properties:**
+- `string $state` - Overall state
+- `string $sha` - Commit SHA
+- `int $totalCount` - Total number of checks
+- `array<GithubCommitStatus> $statuses` - Individual statuses
+
+### GithubCheckRun
+
+Represents a GitHub Actions check run.
+
+**Properties:**
+- `int $id` - Check run ID
+- `string $name` - Check name
+- `string $status` - Status: 'queued', 'in_progress', 'completed'
+- `string $conclusion` - Conclusion: 'success', 'failure', 'neutral', 'cancelled', 'skipped', 'timed_out', 'action_required'
+- `string $headSha` - Commit SHA
+- `string $htmlUrl` - Web URL
+- `string $detailsUrl` - Details URL
+- `string $startedAt` - Start timestamp
+- `string $completedAt` - Completion timestamp
+
+### MergeResult
+
+Represents the result of a merge operation.
+
+**Properties:**
+- `string $sha` - Merge commit SHA
+- `bool $merged` - Was merge successful
+- `string $message` - Result message
+
+## Collections
+
+All collection classes implement `Iterator` and `Countable` interfaces.
+
+- `GithubRepositoryList` - Collection of repositories
+- `GithubPullRequestList` - Collection of pull requests
+- `GithubCommentList` - Collection of comments
+- `GithubReviewList` - Collection of reviews
+- `GithubLabelList` - Collection of labels
+- `GithubCheckRunList` - Collection of check runs
+
+**Methods:**
+- `count(): int` - Get number of items
+- `toArray(): array` - Convert to array
+- Plus all standard iterator methods
+
+## DTOs
+
+### CreatePullRequestParams
+
+Data transfer object for creating pull requests.
+
+```php
+public function __construct(
+    public readonly string $title,
+    public readonly string $head,
+    public readonly string $base,
+    public readonly string $body = '',
+    public readonly bool $draft = false,
+    public readonly bool $maintainerCanModify = true
+)
+```
+
+**Parameters:**
+- `$title` - The title of the pull request (required)
+- `$head` - The name of the branch where your changes are (required)
+  - Can be a simple branch name: `'feature-branch'`
+  - Can include owner prefix for forks: `'username:feature-branch'`
+- `$base` - The name of the branch you want changes pulled into (required)
+- `$body` - The description/body of the pull request (optional)
+- `$draft` - Whether to create as a draft PR (optional, default: false)
+- `$maintainerCanModify` - Whether maintainers can modify the PR (optional, default: true)
+
+**Methods:**
+- `toArray(): array` - Convert to API payload
+
+### PullRequestUpdate
+
+Data transfer object for updating pull requests.
+
+```php
+public function __construct(
+    public readonly ?string $title = null,
+    public readonly ?string $body = null,
+    public readonly ?string $base = null,
+    public readonly ?string $state = null
+)
+```
+
+**Methods:**
+- `toArray(): array` - Convert to API payload (excludes null fields)
+- `isEmpty(): bool` - Check if any field is set
+
+### MergePullRequestParams
+
+Data transfer object for merge operations.
+
+```php
+public function __construct(
+    public readonly string $commitTitle = '',
+    public readonly string $commitMessage = '',
+    public readonly string $mergeMethod = 'merge',
+    public readonly string $sha = ''
+)
+```
+
+**Parameters:**
+- `$commitTitle` - Custom commit title
+- `$commitMessage` - Custom commit message
+- `$mergeMethod` - Merge method: 'merge', 'squash', 'rebase'
+- `$sha` - Expected head SHA (for safe merging)
+
+**Methods:**
+- `toArray(): array` - Convert to API payload (excludes defaults)
diff --git a/doc/MIGRATION.md b/doc/MIGRATION.md
new file mode 100644
index 0000000..e2d3560
--- /dev/null
+++ b/doc/MIGRATION.md
@@ -0,0 +1,305 @@
+# Migration Guide
+
+## Upgrading to Enhanced API Version
+
+This guide helps you upgrade from the basic GitHub API client to the enhanced version with comprehensive pull request management capabilities.
+
+## What's New
+
+The enhanced version adds extensive pull request management features:
+
+- **Pull Request Operations**: Get, update, merge, and close pull requests
+- **Comment Management**: Create, read, update, and delete PR comments
+- **Review Management**: List reviews and request reviewers
+- **Status Checks**: Monitor CI/CD pipeline status and check runs
+- **Label Management**: Add, remove, and set labels on issues and PRs
+- **Enhanced Data**: Pull requests now include many additional fields
+
+## Breaking Changes
+
+### StreamFactory Now Optional But Recommended
+
+**Previous:**
+```php
+$client = new GithubApiClient($httpClient, $requestFactory, $config);
+```
+
+**Now (recommended):**
+```php
+$client = new GithubApiClient($httpClient, $requestFactory, $config, $streamFactory);
+```
+
+**Impact:** Methods that create or update resources (POST/PUT/PATCH) require a StreamFactory:
+- `updatePullRequest()`
+- `createPullRequestComment()`
+- `updateComment()`
+- `requestReviewers()`
+- `addLabels()`
+- `setLabels()`
+- `mergePullRequest()`
+
+If you attempt to use these methods without providing a StreamFactory, you'll get an exception with a clear message.
+
+**Action Required:** Pass a PSR-17 StreamFactory implementation to the constructor if you need write operations.
+
+### Enhanced GithubPullRequest Object
+
+The `GithubPullRequest` object now has many additional properties that may be null in older API responses:
+
+**New Properties:**
+- `?string $body` - PR description
+- `bool $draft` - Is draft PR
+- `bool $merged` - Is merged
+- `?string $mergedAt` - Merge timestamp
+- `string $createdAt` - Creation timestamp
+- `string $updatedAt` - Update timestamp
+- `string $headRef` - Head branch
+- `string $baseRef` - Base branch
+- `string $headSha` - Head commit SHA
+- `?GithubUser $author` - PR author
+- `array<GithubLabel> $labels` - Labels
+- `array<GithubUser> $requestedReviewers` - Reviewers
+- `?bool $mergeable` - Mergeable flag
+- `?string $mergeableState` - Mergeable state
+
+**Impact:** If you're serializing or storing PR objects, you may need to handle these new fields.
+
+**Action Required:** Review code that processes `GithubPullRequest` objects. Most code should continue working as the core properties (`number`, `title`, `state`, `htmlUrl`) remain unchanged.
+
+## New Capabilities
+
+### 1. Get Detailed Pull Request Information
+
+```php
+// New method - get complete PR details
+$pr = $client->getPullRequest($repo, 123);
+
+// Now you can access many more fields
+echo "Author: {$pr->author->login}\n";
+echo "Created: {$pr->createdAt}\n";
+echo "Mergeable: " . ($pr->mergeable ? 'Yes' : 'No') . "\n";
+echo "Draft: " . ($pr->draft ? 'Yes' : 'No') . "\n";
+```
+
+### 2. Update Pull Requests
+
+```php
+use Horde\GithubApiClient\PullRequestUpdate;
+
+// Update title
+$update = new PullRequestUpdate(title: 'New Title');
+$client->updatePullRequest($repo, 123, $update);
+
+// Update multiple fields
+$update = new PullRequestUpdate(
+    title: 'New Title',
+    body: 'Updated description',
+    base: 'develop'
+);
+$client->updatePullRequest($repo, 123, $update);
+
+// Close a PR
+$client->closePullRequest($repo, 123);
+```
+
+### 3. Manage Comments
+
+```php
+// List comments
+$comments = $client->listPullRequestComments($repo, 123);
+
+// Create comment
+$comment = $client->createPullRequestComment($repo, 123, 'Great work!');
+
+// Update comment
+$client->updateComment($repo, $comment->id, 'Even better work!');
+
+// Delete comment
+$client->deleteComment($repo, $comment->id);
+```
+
+### 4. Work with Reviews
+
+```php
+// List reviews
+$reviews = $client->listPullRequestReviews($repo, 123);
+foreach ($reviews as $review) {
+    echo "{$review->user->login}: {$review->state}\n";
+}
+
+// Request reviewers
+$client->requestReviewers($repo, 123, ['username1', 'username2']);
+```
+
+### 5. Monitor CI/CD Status
+
+```php
+// Get combined status
+$status = $client->getCombinedStatus($repo, 'main');
+echo "Status: {$status->state}\n";
+
+// List check runs
+$checkRuns = $client->listCheckRuns($repo, 'feature-branch');
+foreach ($checkRuns as $run) {
+    echo "{$run->name}: {$run->conclusion}\n";
+}
+```
+
+### 6. Manage Labels
+
+```php
+// List labels
+$labels = $client->listIssueLabels($repo, 123);
+
+// Add labels
+$client->addLabels($repo, 123, ['bug', 'priority-high']);
+
+// Replace all labels
+$client->setLabels($repo, 123, ['bug', 'in-progress']);
+
+// Remove a label
+$client->removeLabel($repo, 123, 'wontfix');
+```
+
+### 7. Merge Pull Requests
+
+```php
+use Horde\GithubApiClient\MergePullRequestParams;
+
+// Simple merge
+$params = new MergePullRequestParams();
+$result = $client->mergePullRequest($repo, 123, $params);
+
+// Squash merge with custom message
+$params = new MergePullRequestParams(
+    commitTitle: 'feat: add feature X',
+    commitMessage: 'Implements feature X\n\nCloses #123',
+    mergeMethod: 'squash'
+);
+$result = $client->mergePullRequest($repo, 123, $params);
+
+if ($result->merged) {
+    echo "Successfully merged: {$result->sha}\n";
+}
+```
+
+## Gradual Migration Strategy
+
+You can adopt the new features gradually:
+
+### Phase 1: Update Constructor (Optional)
+Add StreamFactory to enable write operations:
+```php
+$client = new GithubApiClient(
+    $httpClient,
+    $requestFactory,
+    $config,
+    $streamFactory  // Add this
+);
+```
+
+### Phase 2: Use New Read Operations
+Start using new read-only methods that don't require StreamFactory:
+- `getPullRequest()`
+- `listPullRequestComments()`
+- `listPullRequestReviews()`
+- `getCombinedStatus()`
+- `listCheckRuns()`
+- `listIssueLabels()`
+
+### Phase 3: Add Write Operations
+Once StreamFactory is added, use write operations:
+- `updatePullRequest()`
+- `createPullRequestComment()`
+- `requestReviewers()`
+- `addLabels()`
+- `mergePullRequest()`
+
+## Testing Your Upgrade
+
+1. **Add StreamFactory:**
+   ```php
+   use Horde\Http\StreamFactory;
+   $streamFactory = new StreamFactory();
+   ```
+
+2. **Update client instantiation:**
+   ```php
+   $client = new GithubApiClient(
+       $httpClient,
+       $requestFactory,
+       $config,
+       $streamFactory
+   );
+   ```
+
+3. **Test basic operations still work:**
+   ```php
+   // Existing functionality should still work
+   $repos = $client->listRepositoriesInOrganization($org);
+   $pullRequests = $client->listPullRequests($repo);
+   ```
+
+4. **Try new features:**
+   ```php
+   // New functionality
+   $pr = $client->getPullRequest($repo, 1);
+   $comments = $client->listPullRequestComments($repo, 1);
+   ```
+
+## Backwards Compatibility
+
+The enhanced version maintains backwards compatibility for:
+- All existing method signatures
+- Core `GithubPullRequest` properties (`number`, `title`, `state`, `htmlUrl`)
+- Repository listing functionality
+- Basic pull request listing
+
+The only change that may require code updates is adding the StreamFactory parameter if you want to use write operations.
+
+## Getting Help
+
+- See [README.md](README.md) for comprehensive usage examples
+- See [API.md](API.md) for complete API reference
+- Run `bin/demo-client.php` to see working examples
+
+## Troubleshooting
+
+### "StreamFactory is required" Exception
+
+**Problem:** Trying to use a write operation without StreamFactory.
+
+**Solution:** Add StreamFactory to the constructor:
+```php
+use Horde\Http\StreamFactory;
+$client = new GithubApiClient(
+    $httpClient,
+    $requestFactory,
+    $config,
+    new StreamFactory()  // Add this
+);
+```
+
+### Unexpected Properties on GithubPullRequest
+
+**Problem:** Code breaks when encountering new PR properties.
+
+**Solution:** The new properties are additions, not changes. Ensure your code only accesses the properties it needs and handles null values appropriately:
+```php
+// Safe
+$title = $pr->title;  // Always present
+
+// Also safe
+$author = $pr->author?->login ?? 'Unknown';  // Nullable
+```
+
+### Missing Type Declarations
+
+**Problem:** Type errors when passing parameters.
+
+**Solution:** Use the correct types:
+- Repository: `GithubRepository` object
+- Update parameters: `PullRequestUpdate` DTO
+- Merge parameters: `MergePullRequestParams` DTO
+- Numbers: `int` (not string)
+- Labels: `array<string>` (not comma-separated string)
diff --git a/phpunit.xml b/phpunit.xml
index 1a3bdf0..bd9744f 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -14,7 +14,7 @@
          colors="true">
     <testsuites>
         <testsuite name="unit">
-            <directory>tests/unit</directory>
+            <directory>test/unit</directory>
         </testsuite>
     </testsuites>
 
diff --git a/src/AddLabelsRequestFactory.php b/src/AddLabelsRequestFactory.php
new file mode 100644
index 0000000..d18303b
--- /dev/null
+++ b/src/AddLabelsRequestFactory.php
@@ -0,0 +1,62 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+
+/**
+ * Factory for creating requests to add labels to an issue/PR
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class AddLabelsRequestFactory
+{
+    /**
+     * @param array<string> $labels Label names to add
+     */
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly StreamFactoryInterface $streamFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $issueNumber,
+        private readonly array $labels
+    ) {}
+
+    /**
+     * Create HTTP request to add labels
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/issues/%d/labels',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->issueNumber
+        );
+
+        $jsonBody = json_encode(['labels' => $this->labels], JSON_THROW_ON_ERROR);
+        $stream = $this->streamFactory->createStream($jsonBody);
+
+        $request = $this->requestFactory->createRequest('POST', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+        $request = $request->withHeader('Content-Type', 'application/json');
+        $request = $request->withBody($stream);
+
+        return $request;
+    }
+}
diff --git a/src/CreatePullRequestCommentRequestFactory.php b/src/CreatePullRequestCommentRequestFactory.php
new file mode 100644
index 0000000..02fb825
--- /dev/null
+++ b/src/CreatePullRequestCommentRequestFactory.php
@@ -0,0 +1,59 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+
+/**
+ * Factory for creating requests to create pull request comments
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class CreatePullRequestCommentRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly StreamFactoryInterface $streamFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $pullNumber,
+        private readonly string $body
+    ) {}
+
+    /**
+     * Create HTTP request to create a pull request comment
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/issues/%d/comments',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->pullNumber
+        );
+
+        $jsonBody = json_encode(['body' => $this->body], JSON_THROW_ON_ERROR);
+        $stream = $this->streamFactory->createStream($jsonBody);
+
+        $request = $this->requestFactory->createRequest('POST', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+        $request = $request->withHeader('Content-Type', 'application/json');
+        $request = $request->withBody($stream);
+
+        return $request;
+    }
+}
diff --git a/src/CreatePullRequestParams.php b/src/CreatePullRequestParams.php
new file mode 100644
index 0000000..5c04d74
--- /dev/null
+++ b/src/CreatePullRequestParams.php
@@ -0,0 +1,62 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+/**
+ * Data transfer object for creating a pull request
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class CreatePullRequestParams
+{
+    /**
+     * @param string $title The title of the pull request (required)
+     * @param string $head The name of the branch where your changes are implemented (required)
+     * @param string $base The name of the branch you want the changes pulled into (required)
+     * @param string $body The contents of the pull request (optional)
+     * @param bool $draft Whether to create the pull request as a draft (optional, default: false)
+     * @param bool $maintainerCanModify Whether maintainers can modify the pull request (optional, default: true)
+     */
+    public function __construct(
+        public readonly string $title,
+        public readonly string $head,
+        public readonly string $base,
+        public readonly string $body = '',
+        public readonly bool $draft = false,
+        public readonly bool $maintainerCanModify = true
+    ) {}
+
+    /**
+     * Convert to array for API request
+     *
+     * @return array<string, string|bool>
+     */
+    public function toArray(): array
+    {
+        $data = [
+            'title' => $this->title,
+            'head' => $this->head,
+            'base' => $this->base,
+            'maintainer_can_modify' => $this->maintainerCanModify,
+        ];
+
+        if ($this->body !== '') {
+            $data['body'] = $this->body;
+        }
+
+        if ($this->draft) {
+            $data['draft'] = true;
+        }
+
+        return $data;
+    }
+}
diff --git a/src/CreatePullRequestRequestFactory.php b/src/CreatePullRequestRequestFactory.php
new file mode 100644
index 0000000..edc72b6
--- /dev/null
+++ b/src/CreatePullRequestRequestFactory.php
@@ -0,0 +1,57 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+
+/**
+ * Factory for creating requests to create a pull request
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class CreatePullRequestRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly StreamFactoryInterface $streamFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly CreatePullRequestParams $params
+    ) {}
+
+    /**
+     * Create HTTP request to create a pull request
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/pulls',
+            $this->repo->owner,
+            $this->repo->name
+        );
+
+        $jsonBody = json_encode($this->params->toArray(), JSON_THROW_ON_ERROR);
+        $stream = $this->streamFactory->createStream($jsonBody);
+
+        $request = $this->requestFactory->createRequest('POST', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+        $request = $request->withHeader('Content-Type', 'application/json');
+        $request = $request->withBody($stream);
+
+        return $request;
+    }
+}
diff --git a/src/DeleteCommentRequestFactory.php b/src/DeleteCommentRequestFactory.php
new file mode 100644
index 0000000..8163faf
--- /dev/null
+++ b/src/DeleteCommentRequestFactory.php
@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Factory for creating requests to delete a comment
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class DeleteCommentRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $commentId
+    ) {}
+
+    /**
+     * Create HTTP request to delete a comment
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/issues/comments/%d',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->commentId
+        );
+
+        $request = $this->requestFactory->createRequest('DELETE', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+
+        return $request;
+    }
+}
diff --git a/src/GetCombinedStatusRequestFactory.php b/src/GetCombinedStatusRequestFactory.php
new file mode 100644
index 0000000..e654350
--- /dev/null
+++ b/src/GetCombinedStatusRequestFactory.php
@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Factory for creating requests to get combined commit status
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GetCombinedStatusRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly string $ref
+    ) {}
+
+    /**
+     * Create HTTP request to get combined status
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/commits/%s/status',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->ref
+        );
+
+        $request = $this->requestFactory->createRequest('GET', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+
+        return $request;
+    }
+}
diff --git a/src/GetPullRequestRequestFactory.php b/src/GetPullRequestRequestFactory.php
new file mode 100644
index 0000000..a3f9cd2
--- /dev/null
+++ b/src/GetPullRequestRequestFactory.php
@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Factory for creating requests to get a single pull request
+ *
+ * Copyright 2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GetPullRequestRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $pullNumber
+    ) {}
+
+    /**
+     * Create HTTP request to get a single pull request
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/pulls/%d',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->pullNumber
+        );
+
+        $request = $this->requestFactory->createRequest('GET', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+
+        return $request;
+    }
+}
diff --git a/src/GithubApiClient.php b/src/GithubApiClient.php
index 2ef3629..c3c36b5 100644
--- a/src/GithubApiClient.php
+++ b/src/GithubApiClient.php
@@ -7,6 +7,7 @@
 use Horde\Http\RequestFactory;
 use Psr\Http\Client\ClientInterface;
 use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\StreamFactoryInterface;
 use Exception;
 use Stringable;
 use OutOfBoundsException;
@@ -16,7 +17,8 @@ class GithubApiClient
     public function __construct(
         private readonly ClientInterface $httpClient,
         private readonly RequestFactoryInterface $requestFactory,
-        private readonly GithubApiConfig $config
+        private readonly GithubApiConfig $config,
+        private readonly ?StreamFactoryInterface $streamFactory = null
     ) {}
 
     public function listRepositoriesInOrganization(GithubOrganizationId $org): GithubRepositoryList
@@ -102,6 +104,555 @@ public function getTokenScopes(): TokenScopes
         }
     }
 
+    /**
+     * Get a single pull request with complete details
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The pull request number
+     * @return GithubPullRequest
+     * @throws Exception
+     */
+    public function getPullRequest(GithubRepository $repo, int $number): GithubPullRequest
+    {
+        $requestFactory = new GetPullRequestRequestFactory(
+            $this->requestFactory,
+            $this->config,
+            $repo,
+            $number
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            $prFactory = new GithubPullRequestFactory();
+            return $prFactory->createFromApiResponse($data);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Update a pull request (title, body, base, or state)
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The pull request number
+     * @param PullRequestUpdate $update The fields to update
+     * @return GithubPullRequest The updated pull request
+     * @throws Exception
+     */
+    public function updatePullRequest(GithubRepository $repo, int $number, PullRequestUpdate $update): GithubPullRequest
+    {
+        if ($this->streamFactory === null) {
+            throw new Exception('StreamFactory is required for updatePullRequest. Please provide it in the constructor.');
+        }
+
+        $requestFactory = new UpdatePullRequestRequestFactory(
+            $this->requestFactory,
+            $this->streamFactory,
+            $this->config,
+            $repo,
+            $number,
+            $update
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            $prFactory = new GithubPullRequestFactory();
+            return $prFactory->createFromApiResponse($data);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * List all comments on a pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The pull request number
+     * @return GithubCommentList
+     * @throws Exception
+     */
+    public function listPullRequestComments(GithubRepository $repo, int $number): GithubCommentList
+    {
+        $requestFactory = new ListPullRequestCommentsRequestFactory(
+            $this->requestFactory,
+            $this->config,
+            $repo,
+            $number
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            $commentFactory = new GithubCommentFactory();
+            $comments = [];
+            foreach ($data as $commentData) {
+                $comments[] = $commentFactory->createFromApiResponse($commentData);
+            }
+            return new GithubCommentList($comments);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Create a comment on a pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The pull request number
+     * @param string $body The comment body
+     * @return GithubComment The created comment
+     * @throws Exception
+     */
+    public function createPullRequestComment(GithubRepository $repo, int $number, string $body): GithubComment
+    {
+        if ($this->streamFactory === null) {
+            throw new Exception('StreamFactory is required for createPullRequestComment. Please provide it in the constructor.');
+        }
+
+        $requestFactory = new CreatePullRequestCommentRequestFactory(
+            $this->requestFactory,
+            $this->streamFactory,
+            $this->config,
+            $repo,
+            $number,
+            $body
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 201) {
+            $data = json_decode((string) $response->getBody());
+            $commentFactory = new GithubCommentFactory();
+            return $commentFactory->createFromApiResponse($data);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Update a comment
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $commentId The comment ID
+     * @param string $body The new comment body
+     * @return GithubComment The updated comment
+     * @throws Exception
+     */
+    public function updateComment(GithubRepository $repo, int $commentId, string $body): GithubComment
+    {
+        if ($this->streamFactory === null) {
+            throw new Exception('StreamFactory is required for updateComment. Please provide it in the constructor.');
+        }
+
+        $requestFactory = new UpdateCommentRequestFactory(
+            $this->requestFactory,
+            $this->streamFactory,
+            $this->config,
+            $repo,
+            $commentId,
+            $body
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            $commentFactory = new GithubCommentFactory();
+            return $commentFactory->createFromApiResponse($data);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Delete a comment
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $commentId The comment ID
+     * @return void
+     * @throws Exception
+     */
+    public function deleteComment(GithubRepository $repo, int $commentId): void
+    {
+        $requestFactory = new DeleteCommentRequestFactory(
+            $this->requestFactory,
+            $this->config,
+            $repo,
+            $commentId
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() !== 204) {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * List all reviews on a pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The pull request number
+     * @return GithubReviewList
+     * @throws Exception
+     */
+    public function listPullRequestReviews(GithubRepository $repo, int $number): GithubReviewList
+    {
+        $requestFactory = new ListPullRequestReviewsRequestFactory(
+            $this->requestFactory,
+            $this->config,
+            $repo,
+            $number
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            $reviewFactory = new GithubReviewFactory();
+            $reviews = [];
+            foreach ($data as $reviewData) {
+                $reviews[] = $reviewFactory->createFromApiResponse($reviewData);
+            }
+            return new GithubReviewList($reviews);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Request reviewers for a pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The pull request number
+     * @param array<string> $reviewers User logins to request as reviewers
+     * @param array<string> $teamReviewers Team slugs to request as reviewers
+     * @return GithubPullRequest The updated pull request
+     * @throws Exception
+     */
+    public function requestReviewers(GithubRepository $repo, int $number, array $reviewers = [], array $teamReviewers = []): GithubPullRequest
+    {
+        if ($this->streamFactory === null) {
+            throw new Exception('StreamFactory is required for requestReviewers. Please provide it in the constructor.');
+        }
+
+        $requestFactory = new RequestReviewersRequestFactory(
+            $this->requestFactory,
+            $this->streamFactory,
+            $this->config,
+            $repo,
+            $number,
+            $reviewers,
+            $teamReviewers
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 201) {
+            $data = json_decode((string) $response->getBody());
+            $prFactory = new GithubPullRequestFactory();
+            return $prFactory->createFromApiResponse($data);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Get combined status for a commit
+     *
+     * @param GithubRepository $repo The repository
+     * @param string $ref The commit SHA, branch name, or tag name
+     * @return GithubCombinedStatus
+     * @throws Exception
+     */
+    public function getCombinedStatus(GithubRepository $repo, string $ref): GithubCombinedStatus
+    {
+        $requestFactory = new GetCombinedStatusRequestFactory(
+            $this->requestFactory,
+            $this->config,
+            $repo,
+            $ref
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            return GithubCombinedStatus::fromApiResponse($data);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * List check runs for a commit
+     *
+     * @param GithubRepository $repo The repository
+     * @param string $ref The commit SHA, branch name, or tag name
+     * @return GithubCheckRunList
+     * @throws Exception
+     */
+    public function listCheckRuns(GithubRepository $repo, string $ref): GithubCheckRunList
+    {
+        $requestFactory = new ListCheckRunsRequestFactory(
+            $this->requestFactory,
+            $this->config,
+            $repo,
+            $ref
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            $checkRuns = [];
+            if (isset($data->check_runs) && is_array($data->check_runs)) {
+                foreach ($data->check_runs as $checkRunData) {
+                    $checkRuns[] = GithubCheckRun::fromApiResponse($checkRunData);
+                }
+            }
+            return new GithubCheckRunList($checkRuns);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * List labels on an issue or pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The issue or pull request number
+     * @return GithubLabelList
+     * @throws Exception
+     */
+    public function listIssueLabels(GithubRepository $repo, int $number): GithubLabelList
+    {
+        $requestFactory = new ListIssueLabelsRequestFactory(
+            $this->requestFactory,
+            $this->config,
+            $repo,
+            $number
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            $labelFactory = new GithubLabelFactory();
+            $labels = [];
+            foreach ($data as $labelData) {
+                $labels[] = $labelFactory->createFromApiResponse($labelData);
+            }
+            return new GithubLabelList($labels);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Add labels to an issue or pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The issue or pull request number
+     * @param array<string> $labels Label names to add
+     * @return GithubLabelList The updated list of labels
+     * @throws Exception
+     */
+    public function addLabels(GithubRepository $repo, int $number, array $labels): GithubLabelList
+    {
+        if ($this->streamFactory === null) {
+            throw new Exception('StreamFactory is required for addLabels. Please provide it in the constructor.');
+        }
+
+        $requestFactory = new AddLabelsRequestFactory(
+            $this->requestFactory,
+            $this->streamFactory,
+            $this->config,
+            $repo,
+            $number,
+            $labels
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            $labelFactory = new GithubLabelFactory();
+            $labelsList = [];
+            foreach ($data as $labelData) {
+                $labelsList[] = $labelFactory->createFromApiResponse($labelData);
+            }
+            return new GithubLabelList($labelsList);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Set (replace) all labels on an issue or pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The issue or pull request number
+     * @param array<string> $labels Label names to set (replaces all existing labels)
+     * @return GithubLabelList The updated list of labels
+     * @throws Exception
+     */
+    public function setLabels(GithubRepository $repo, int $number, array $labels): GithubLabelList
+    {
+        if ($this->streamFactory === null) {
+            throw new Exception('StreamFactory is required for setLabels. Please provide it in the constructor.');
+        }
+
+        $requestFactory = new SetLabelsRequestFactory(
+            $this->requestFactory,
+            $this->streamFactory,
+            $this->config,
+            $repo,
+            $number,
+            $labels
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            $labelFactory = new GithubLabelFactory();
+            $labelsList = [];
+            foreach ($data as $labelData) {
+                $labelsList[] = $labelFactory->createFromApiResponse($labelData);
+            }
+            return new GithubLabelList($labelsList);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Remove a label from an issue or pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The issue or pull request number
+     * @param string $labelName The name of the label to remove
+     * @return void
+     * @throws Exception
+     */
+    public function removeLabel(GithubRepository $repo, int $number, string $labelName): void
+    {
+        $requestFactory = new RemoveLabelRequestFactory(
+            $this->requestFactory,
+            $this->config,
+            $repo,
+            $number,
+            $labelName
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() !== 200) {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Merge a pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The pull request number
+     * @param MergePullRequestParams $params Merge parameters
+     * @return MergeResult The result of the merge operation
+     * @throws Exception
+     */
+    public function mergePullRequest(GithubRepository $repo, int $number, MergePullRequestParams $params): MergeResult
+    {
+        if ($this->streamFactory === null) {
+            throw new Exception('StreamFactory is required for mergePullRequest. Please provide it in the constructor.');
+        }
+
+        $requestFactory = new MergePullRequestRequestFactory(
+            $this->requestFactory,
+            $this->streamFactory,
+            $this->config,
+            $repo,
+            $number,
+            $params
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 200) {
+            $data = json_decode((string) $response->getBody());
+            return MergeResult::fromApiResponse($data);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
+    /**
+     * Close a pull request without merging
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The pull request number
+     * @return GithubPullRequest The closed pull request
+     * @throws Exception
+     */
+    public function closePullRequest(GithubRepository $repo, int $number): GithubPullRequest
+    {
+        $update = new PullRequestUpdate(state: 'closed');
+        return $this->updatePullRequest($repo, $number, $update);
+    }
+
+    /**
+     * Reopen a closed pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param int $number The pull request number
+     * @return GithubPullRequest The reopened pull request
+     * @throws Exception
+     */
+    public function reopenPullRequest(GithubRepository $repo, int $number): GithubPullRequest
+    {
+        $update = new PullRequestUpdate(state: 'open');
+        return $this->updatePullRequest($repo, $number, $update);
+    }
+
+    /**
+     * Create a new pull request
+     *
+     * @param GithubRepository $repo The repository
+     * @param CreatePullRequestParams $params The pull request parameters
+     * @return GithubPullRequest The created pull request
+     * @throws Exception
+     */
+    public function createPullRequest(GithubRepository $repo, CreatePullRequestParams $params): GithubPullRequest
+    {
+        if ($this->streamFactory === null) {
+            throw new Exception('StreamFactory is required for createPullRequest. Please provide it in the constructor.');
+        }
+
+        $requestFactory = new CreatePullRequestRequestFactory(
+            $this->requestFactory,
+            $this->streamFactory,
+            $this->config,
+            $repo,
+            $params
+        );
+        $request = $requestFactory->create();
+        $response = $this->httpClient->sendRequest($request);
+
+        if ($response->getStatusCode() === 201) {
+            $data = json_decode((string) $response->getBody());
+            $prFactory = new GithubPullRequestFactory();
+            return $prFactory->createFromApiResponse($data);
+        } else {
+            throw new Exception($response->getStatusCode() . ' ' . $response->getReasonPhrase());
+        }
+    }
+
     /**
      * @param array<mixed> $repos
      * @param string $json
diff --git a/src/GithubCheckRun.php b/src/GithubCheckRun.php
new file mode 100644
index 0000000..f525955
--- /dev/null
+++ b/src/GithubCheckRun.php
@@ -0,0 +1,60 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Stringable;
+
+/**
+ * Represents a GitHub check run
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubCheckRun implements Stringable
+{
+    public function __construct(
+        public readonly int $id,
+        public readonly string $name,
+        public readonly string $status,
+        public readonly string $conclusion,
+        public readonly string $headSha,
+        public readonly string $htmlUrl,
+        public readonly string $detailsUrl,
+        public readonly string $startedAt,
+        public readonly string $completedAt
+    ) {}
+
+    public function __toString(): string
+    {
+        return sprintf('%s: %s/%s', $this->name, $this->status, $this->conclusion);
+    }
+
+    /**
+     * Create from GitHub API response
+     *
+     * @param object $data The API response data
+     * @return self
+     */
+    public static function fromApiResponse(object $data): self
+    {
+        return new self(
+            id: $data->id ?? 0,
+            name: $data->name ?? '',
+            status: $data->status ?? '',
+            conclusion: $data->conclusion ?? '',
+            headSha: $data->head_sha ?? '',
+            htmlUrl: $data->html_url ?? '',
+            detailsUrl: $data->details_url ?? '',
+            startedAt: $data->started_at ?? '',
+            completedAt: $data->completed_at ?? ''
+        );
+    }
+}
diff --git a/src/GithubCheckRunList.php b/src/GithubCheckRunList.php
new file mode 100644
index 0000000..139ef73
--- /dev/null
+++ b/src/GithubCheckRunList.php
@@ -0,0 +1,71 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Iterator;
+use Countable;
+
+/**
+ * Collection of GitHub check runs
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ * @implements Iterator<int, GithubCheckRun>
+ */
+class GithubCheckRunList implements Iterator, Countable
+{
+    private int $position = 0;
+
+    /**
+     * @param array<GithubCheckRun> $checkRuns
+     */
+    public function __construct(
+        private readonly array $checkRuns
+    ) {}
+
+    public function current(): GithubCheckRun
+    {
+        return $this->checkRuns[$this->position];
+    }
+
+    public function key(): int
+    {
+        return $this->position;
+    }
+
+    public function next(): void
+    {
+        ++$this->position;
+    }
+
+    public function rewind(): void
+    {
+        $this->position = 0;
+    }
+
+    public function valid(): bool
+    {
+        return isset($this->checkRuns[$this->position]);
+    }
+
+    public function count(): int
+    {
+        return count($this->checkRuns);
+    }
+
+    /**
+     * @return array<GithubCheckRun>
+     */
+    public function toArray(): array
+    {
+        return $this->checkRuns;
+    }
+}
diff --git a/src/GithubCombinedStatus.php b/src/GithubCombinedStatus.php
new file mode 100644
index 0000000..3f68e04
--- /dev/null
+++ b/src/GithubCombinedStatus.php
@@ -0,0 +1,60 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Stringable;
+
+/**
+ * Represents the combined status of all checks for a commit
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubCombinedStatus implements Stringable
+{
+    /**
+     * @param array<GithubCommitStatus> $statuses
+     */
+    public function __construct(
+        public readonly string $state,
+        public readonly string $sha,
+        public readonly int $totalCount,
+        public readonly array $statuses
+    ) {}
+
+    public function __toString(): string
+    {
+        return sprintf('%s (%d checks)', $this->state, $this->totalCount);
+    }
+
+    /**
+     * Create from GitHub API response
+     *
+     * @param object $data The API response data
+     * @return self
+     */
+    public static function fromApiResponse(object $data): self
+    {
+        $statuses = [];
+        if (isset($data->statuses) && is_array($data->statuses)) {
+            foreach ($data->statuses as $statusData) {
+                $statuses[] = GithubCommitStatus::fromApiResponse($statusData);
+            }
+        }
+
+        return new self(
+            state: $data->state ?? '',
+            sha: $data->sha ?? '',
+            totalCount: $data->total_count ?? 0,
+            statuses: $statuses
+        );
+    }
+}
diff --git a/src/GithubComment.php b/src/GithubComment.php
new file mode 100644
index 0000000..c8ac31b
--- /dev/null
+++ b/src/GithubComment.php
@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Stringable;
+
+/**
+ * Represents a GitHub pull request comment
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubComment implements Stringable
+{
+    public function __construct(
+        public readonly int $id,
+        public readonly string $body,
+        public readonly GithubUser $author,
+        public readonly string $createdAt,
+        public readonly string $updatedAt,
+        public readonly string $htmlUrl,
+        public readonly string $apiUrl
+    ) {}
+
+    public function __toString(): string
+    {
+        return $this->htmlUrl;
+    }
+
+    /**
+     * Create GithubComment from GitHub API response
+     *
+     * @param object $data Decoded JSON from API
+     * @return self
+     */
+    public static function fromApiResponse(object $data): self
+    {
+        $userFactory = new GithubUserFactory();
+
+        return new self(
+            id: $data->id ?? 0,
+            body: $data->body ?? '',
+            author: $userFactory->createFromApiResponse($data->user),
+            createdAt: $data->created_at ?? '',
+            updatedAt: $data->updated_at ?? '',
+            htmlUrl: $data->html_url ?? '',
+            apiUrl: $data->url ?? ''
+        );
+    }
+}
diff --git a/src/GithubCommentFactory.php b/src/GithubCommentFactory.php
new file mode 100644
index 0000000..333fff6
--- /dev/null
+++ b/src/GithubCommentFactory.php
@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+/**
+ * Factory for creating GithubComment objects from API responses
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubCommentFactory
+{
+    /**
+     * Create GithubComment from GitHub API response
+     *
+     * @param object $data Decoded JSON comment object from API
+     * @return GithubComment
+     */
+    public function createFromApiResponse(object $data): GithubComment
+    {
+        return GithubComment::fromApiResponse($data);
+    }
+}
diff --git a/src/GithubCommentList.php b/src/GithubCommentList.php
new file mode 100644
index 0000000..1ef2eb7
--- /dev/null
+++ b/src/GithubCommentList.php
@@ -0,0 +1,72 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Countable;
+use Iterator;
+
+/**
+ * Collection of GitHub comments
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubCommentList implements Iterator, Countable
+{
+    private int $position = 0;
+
+    /**
+     * @param array<GithubComment> $comments
+     */
+    public function __construct(
+        private array $comments = []
+    ) {}
+
+    public function current(): GithubComment
+    {
+        return $this->comments[$this->position];
+    }
+
+    public function key(): int
+    {
+        return $this->position;
+    }
+
+    public function next(): void
+    {
+        ++$this->position;
+    }
+
+    public function rewind(): void
+    {
+        $this->position = 0;
+    }
+
+    public function valid(): bool
+    {
+        return isset($this->comments[$this->position]);
+    }
+
+    public function count(): int
+    {
+        return count($this->comments);
+    }
+
+    /**
+     * Get all comments as array
+     *
+     * @return array<GithubComment>
+     */
+    public function toArray(): array
+    {
+        return $this->comments;
+    }
+}
diff --git a/src/GithubCommitStatus.php b/src/GithubCommitStatus.php
new file mode 100644
index 0000000..8c66af5
--- /dev/null
+++ b/src/GithubCommitStatus.php
@@ -0,0 +1,54 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Stringable;
+
+/**
+ * Represents a GitHub commit status
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubCommitStatus implements Stringable
+{
+    public function __construct(
+        public readonly string $state,
+        public readonly string $context,
+        public readonly string $description,
+        public readonly string $targetUrl,
+        public readonly string $createdAt,
+        public readonly string $updatedAt
+    ) {}
+
+    public function __toString(): string
+    {
+        return sprintf('%s: %s (%s)', $this->context, $this->state, $this->description);
+    }
+
+    /**
+     * Create from GitHub API response
+     *
+     * @param object $data The API response data
+     * @return self
+     */
+    public static function fromApiResponse(object $data): self
+    {
+        return new self(
+            state: $data->state ?? '',
+            context: $data->context ?? '',
+            description: $data->description ?? '',
+            targetUrl: $data->target_url ?? '',
+            createdAt: $data->created_at ?? '',
+            updatedAt: $data->updated_at ?? ''
+        );
+    }
+}
diff --git a/src/GithubLabel.php b/src/GithubLabel.php
new file mode 100644
index 0000000..899aa63
--- /dev/null
+++ b/src/GithubLabel.php
@@ -0,0 +1,48 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Stringable;
+
+/**
+ * Represents a GitHub label
+ *
+ * Copyright 2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubLabel implements Stringable
+{
+    public function __construct(
+        public readonly string $name,
+        public readonly string $color,
+        public readonly ?string $description = null
+    ) {}
+
+    public function __toString(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Create GithubLabel from GitHub API response
+     *
+     * @param object $data Decoded JSON from API
+     * @return self
+     */
+    public static function fromApiResponse(object $data): self
+    {
+        return new self(
+            name: $data->name ?? '',
+            color: $data->color ?? '000000',
+            description: $data->description ?? null
+        );
+    }
+}
diff --git a/src/GithubLabelFactory.php b/src/GithubLabelFactory.php
new file mode 100644
index 0000000..3a7098c
--- /dev/null
+++ b/src/GithubLabelFactory.php
@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+/**
+ * Factory for creating GithubLabel objects from API responses
+ *
+ * Copyright 2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubLabelFactory
+{
+    /**
+     * Create GithubLabel from GitHub API response
+     *
+     * @param object $data Decoded JSON label object from API
+     * @return GithubLabel
+     */
+    public function createFromApiResponse(object $data): GithubLabel
+    {
+        return GithubLabel::fromApiResponse($data);
+    }
+}
diff --git a/src/GithubLabelList.php b/src/GithubLabelList.php
new file mode 100644
index 0000000..572e861
--- /dev/null
+++ b/src/GithubLabelList.php
@@ -0,0 +1,71 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Iterator;
+use Countable;
+
+/**
+ * Collection of GitHub labels
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ * @implements Iterator<int, GithubLabel>
+ */
+class GithubLabelList implements Iterator, Countable
+{
+    private int $position = 0;
+
+    /**
+     * @param array<GithubLabel> $labels
+     */
+    public function __construct(
+        private readonly array $labels
+    ) {}
+
+    public function current(): GithubLabel
+    {
+        return $this->labels[$this->position];
+    }
+
+    public function key(): int
+    {
+        return $this->position;
+    }
+
+    public function next(): void
+    {
+        ++$this->position;
+    }
+
+    public function rewind(): void
+    {
+        $this->position = 0;
+    }
+
+    public function valid(): bool
+    {
+        return isset($this->labels[$this->position]);
+    }
+
+    public function count(): int
+    {
+        return count($this->labels);
+    }
+
+    /**
+     * @return array<GithubLabel>
+     */
+    public function toArray(): array
+    {
+        return $this->labels;
+    }
+}
diff --git a/src/GithubPullRequest.php b/src/GithubPullRequest.php
index 0a50ac9..c10c045 100644
--- a/src/GithubPullRequest.php
+++ b/src/GithubPullRequest.php
@@ -8,20 +8,86 @@
 use Stringable;
 use InvalidArgumentException;
 
+/**
+ * Represents a GitHub Pull Request
+ *
+ * Copyright 2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
 class GithubPullRequest implements Stringable
 {
+    /**
+     * Constructor - typically not called directly, use fromApiResponse() instead
+     *
+     * @internal This constructor has 20 parameters and should not be called directly by users.
+     *           Use GithubPullRequest::fromApiResponse() or retrieve PRs via GithubApiClient methods.
+     *
+     * @param int $number PR number
+     * @param string $title PR title
+     * @param string $body PR description/body
+     * @param string $htmlUrl PR web URL
+     * @param string $apiUrl PR API URL
+     * @param string $state open, closed
+     * @param bool $draft Is draft PR
+     * @param bool $merged Has been merged
+     * @param ?string $mergedAt Merge timestamp (ISO 8601)
+     * @param string $createdAt Creation timestamp (ISO 8601)
+     * @param string $updatedAt Last update timestamp (ISO 8601)
+     * @param GithubRepository $baseRepo Base repository
+     * @param GithubRepository $headRepo Head repository
+     * @param string $baseBranch Base branch name
+     * @param string $headBranch Head branch name
+     * @param GithubUser $author PR author
+     * @param array<GithubLabel> $labels Labels on PR
+     * @param array<GithubUser> $requestedReviewers Requested reviewers
+     * @param ?string $mergeableState Mergeable state (clean, dirty, unstable, blocked, unknown)
+     * @param ?bool $mergeable Can be merged
+     */
     public function __construct(
         public readonly int $number,
         public readonly string $title,
+        public readonly string $body,
         public readonly string $htmlUrl,
         public readonly string $apiUrl,
         public readonly string $state,
+        public readonly bool $draft,
+        public readonly bool $merged,
+        public readonly ?string $mergedAt,
+        public readonly string $createdAt,
+        public readonly string $updatedAt,
         public readonly GithubRepository $baseRepo,
         public readonly GithubRepository $headRepo,
+        public readonly string $baseBranch,
+        public readonly string $headBranch,
+        public readonly GithubUser $author,
+        public readonly array $labels,
+        public readonly array $requestedReviewers,
+        public readonly ?string $mergeableState,
+        public readonly ?bool $mergeable,
     ) {}
 
     public function __toString(): string
     {
         return $this->htmlUrl;
     }
+
+    /**
+     * Create GithubPullRequest from GitHub API response
+     *
+     * This is the recommended way to create GithubPullRequest objects.
+     *
+     * @param object $data Decoded JSON from GitHub API
+     * @return self
+     */
+    public static function fromApiResponse(object $data): self
+    {
+        $factory = new GithubPullRequestFactory();
+        return $factory->createFromApiResponse($data);
+    }
 }
diff --git a/src/GithubPullRequestFactory.php b/src/GithubPullRequestFactory.php
index a483260..5bdc33a 100644
--- a/src/GithubPullRequestFactory.php
+++ b/src/GithubPullRequestFactory.php
@@ -7,18 +7,68 @@
 use stdClass;
 use InvalidArgumentException;
 
+/**
+ * Factory for creating GithubPullRequest objects from API responses
+ *
+ * Copyright 2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
 class GithubPullRequestFactory
 {
+    private GithubUserFactory $userFactory;
+    private GithubLabelFactory $labelFactory;
+
+    public function __construct()
+    {
+        $this->userFactory = new GithubUserFactory();
+        $this->labelFactory = new GithubLabelFactory();
+    }
+
     public function createFromApiResponse(stdClass $apiResponse): GithubPullRequest
     {
+        // Parse labels
+        $labels = [];
+        if (isset($apiResponse->labels) && is_array($apiResponse->labels)) {
+            foreach ($apiResponse->labels as $labelData) {
+                $labels[] = $this->labelFactory->createFromApiResponse($labelData);
+            }
+        }
+
+        // Parse requested reviewers
+        $requestedReviewers = [];
+        if (isset($apiResponse->requested_reviewers) && is_array($apiResponse->requested_reviewers)) {
+            foreach ($apiResponse->requested_reviewers as $reviewerData) {
+                $requestedReviewers[] = $this->userFactory->createFromApiResponse($reviewerData);
+            }
+        }
+
         return new GithubPullRequest(
             number: $apiResponse->number,
             title: $apiResponse->title,
+            body: $apiResponse->body ?? '',
             htmlUrl: $apiResponse->html_url,
             apiUrl: $apiResponse->url,
             state: $apiResponse->state,
+            draft: $apiResponse->draft ?? false,
+            merged: $apiResponse->merged ?? false,
+            mergedAt: $apiResponse->merged_at ?? null,
+            createdAt: $apiResponse->created_at ?? '',
+            updatedAt: $apiResponse->updated_at ?? '',
             baseRepo: GithubRepository::fromApiArray((array) $apiResponse->base->repo),
             headRepo: GithubRepository::fromApiArray((array) $apiResponse->head->repo),
+            baseBranch: $apiResponse->base->ref ?? '',
+            headBranch: $apiResponse->head->ref ?? '',
+            author: $this->userFactory->createFromApiResponse($apiResponse->user),
+            labels: $labels,
+            requestedReviewers: $requestedReviewers,
+            mergeableState: $apiResponse->mergeable_state ?? null,
+            mergeable: $apiResponse->mergeable ?? null,
         );
     }
 }
diff --git a/src/GithubRepository.php b/src/GithubRepository.php
index 9891e1c..876b2ce 100644
--- a/src/GithubRepository.php
+++ b/src/GithubRepository.php
@@ -10,12 +10,20 @@
 
 class GithubRepository
 {
+    public readonly string $owner;
+    public readonly string $name;
+
     public function __construct(
-        private readonly string $name,
+        string $name,
         private readonly string $fullName,
         private readonly string $description,
         private readonly string $cloneUrl
-    ) {}
+    ) {
+        $this->name = $name;
+        // Extract owner from fullName
+        $parts = explode('/', $fullName, 2);
+        $this->owner = $parts[0] ?? '';
+    }
     public function getName(): string
     {
         return $this->name;
diff --git a/src/GithubReview.php b/src/GithubReview.php
new file mode 100644
index 0000000..603cfc0
--- /dev/null
+++ b/src/GithubReview.php
@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Stringable;
+
+/**
+ * Represents a GitHub pull request review
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubReview implements Stringable
+{
+    public function __construct(
+        public readonly int $id,
+        public readonly GithubUser $user,
+        public readonly string $body,
+        public readonly string $state,
+        public readonly string $htmlUrl,
+        public readonly string $submittedAt,
+        public readonly string $commitId
+    ) {}
+
+    public function __toString(): string
+    {
+        return $this->htmlUrl;
+    }
+
+    /**
+     * Create from GitHub API response
+     *
+     * @param object $data The API response data
+     * @return self
+     */
+    public static function fromApiResponse(object $data): self
+    {
+        $user = isset($data->user) ? GithubUser::fromApiResponse($data->user) : new GithubUser('', 0, '', '', '');
+
+        return new self(
+            id: $data->id ?? 0,
+            user: $user,
+            body: $data->body ?? '',
+            state: $data->state ?? '',
+            htmlUrl: $data->html_url ?? '',
+            submittedAt: $data->submitted_at ?? '',
+            commitId: $data->commit_id ?? ''
+        );
+    }
+}
diff --git a/src/GithubReviewFactory.php b/src/GithubReviewFactory.php
new file mode 100644
index 0000000..1de4a5e
--- /dev/null
+++ b/src/GithubReviewFactory.php
@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+/**
+ * Factory for creating GithubReview instances
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubReviewFactory
+{
+    /**
+     * Create a GithubReview from API response data
+     *
+     * @param object $data The API response data
+     * @return GithubReview
+     */
+    public function createFromApiResponse(object $data): GithubReview
+    {
+        return GithubReview::fromApiResponse($data);
+    }
+}
diff --git a/src/GithubReviewList.php b/src/GithubReviewList.php
new file mode 100644
index 0000000..6e7e357
--- /dev/null
+++ b/src/GithubReviewList.php
@@ -0,0 +1,71 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Iterator;
+use Countable;
+
+/**
+ * Collection of GitHub reviews
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ * @implements Iterator<int, GithubReview>
+ */
+class GithubReviewList implements Iterator, Countable
+{
+    private int $position = 0;
+
+    /**
+     * @param array<GithubReview> $reviews
+     */
+    public function __construct(
+        private readonly array $reviews
+    ) {}
+
+    public function current(): GithubReview
+    {
+        return $this->reviews[$this->position];
+    }
+
+    public function key(): int
+    {
+        return $this->position;
+    }
+
+    public function next(): void
+    {
+        ++$this->position;
+    }
+
+    public function rewind(): void
+    {
+        $this->position = 0;
+    }
+
+    public function valid(): bool
+    {
+        return isset($this->reviews[$this->position]);
+    }
+
+    public function count(): int
+    {
+        return count($this->reviews);
+    }
+
+    /**
+     * @return array<GithubReview>
+     */
+    public function toArray(): array
+    {
+        return $this->reviews;
+    }
+}
diff --git a/src/GithubUser.php b/src/GithubUser.php
new file mode 100644
index 0000000..b4e7a80
--- /dev/null
+++ b/src/GithubUser.php
@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Stringable;
+
+/**
+ * Represents a GitHub user (author, reviewer, commenter, etc.)
+ *
+ * Copyright 2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubUser implements Stringable
+{
+    public function __construct(
+        public readonly string $login,
+        public readonly int $id,
+        public readonly string $avatarUrl,
+        public readonly string $htmlUrl,
+        public readonly string $type = 'User'
+    ) {}
+
+    public function __toString(): string
+    {
+        return $this->login;
+    }
+
+    /**
+     * Create GithubUser from GitHub API response
+     *
+     * @param object $data Decoded JSON from API
+     * @return self
+     */
+    public static function fromApiResponse(object $data): self
+    {
+        return new self(
+            login: $data->login ?? '',
+            id: $data->id ?? 0,
+            avatarUrl: $data->avatar_url ?? '',
+            htmlUrl: $data->html_url ?? '',
+            type: $data->type ?? 'User'
+        );
+    }
+}
diff --git a/src/GithubUserFactory.php b/src/GithubUserFactory.php
new file mode 100644
index 0000000..4ed8760
--- /dev/null
+++ b/src/GithubUserFactory.php
@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+/**
+ * Factory for creating GithubUser objects from API responses
+ *
+ * Copyright 2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class GithubUserFactory
+{
+    /**
+     * Create GithubUser from GitHub API response
+     *
+     * @param object $data Decoded JSON user object from API
+     * @return GithubUser
+     */
+    public function createFromApiResponse(object $data): GithubUser
+    {
+        return GithubUser::fromApiResponse($data);
+    }
+}
diff --git a/src/ListCheckRunsRequestFactory.php b/src/ListCheckRunsRequestFactory.php
new file mode 100644
index 0000000..96604f3
--- /dev/null
+++ b/src/ListCheckRunsRequestFactory.php
@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Factory for creating requests to list check runs for a ref
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class ListCheckRunsRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly string $ref
+    ) {}
+
+    /**
+     * Create HTTP request to list check runs
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/commits/%s/check-runs',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->ref
+        );
+
+        $request = $this->requestFactory->createRequest('GET', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+
+        return $request;
+    }
+}
diff --git a/src/ListIssueLabelsRequestFactory.php b/src/ListIssueLabelsRequestFactory.php
new file mode 100644
index 0000000..601d0bf
--- /dev/null
+++ b/src/ListIssueLabelsRequestFactory.php
@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Factory for creating requests to list labels on an issue/PR
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class ListIssueLabelsRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $issueNumber
+    ) {}
+
+    /**
+     * Create HTTP request to list labels
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/issues/%d/labels',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->issueNumber
+        );
+
+        $request = $this->requestFactory->createRequest('GET', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+
+        return $request;
+    }
+}
diff --git a/src/ListPullRequestCommentsRequestFactory.php b/src/ListPullRequestCommentsRequestFactory.php
new file mode 100644
index 0000000..b3f8fa0
--- /dev/null
+++ b/src/ListPullRequestCommentsRequestFactory.php
@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Factory for creating requests to list pull request comments
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class ListPullRequestCommentsRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $pullNumber
+    ) {}
+
+    /**
+     * Create HTTP request to list pull request comments
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        // Note: GitHub uses the issues endpoint for PR comments
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/issues/%d/comments',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->pullNumber
+        );
+
+        $request = $this->requestFactory->createRequest('GET', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+
+        return $request;
+    }
+}
diff --git a/src/ListPullRequestReviewsRequestFactory.php b/src/ListPullRequestReviewsRequestFactory.php
new file mode 100644
index 0000000..cb388de
--- /dev/null
+++ b/src/ListPullRequestReviewsRequestFactory.php
@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Factory for creating requests to list pull request reviews
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class ListPullRequestReviewsRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $pullNumber
+    ) {}
+
+    /**
+     * Create HTTP request to list pull request reviews
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/pulls/%d/reviews',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->pullNumber
+        );
+
+        $request = $this->requestFactory->createRequest('GET', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+
+        return $request;
+    }
+}
diff --git a/src/MergePullRequestParams.php b/src/MergePullRequestParams.php
new file mode 100644
index 0000000..7ad3cc7
--- /dev/null
+++ b/src/MergePullRequestParams.php
@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+/**
+ * Data transfer object for merge pull request parameters
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class MergePullRequestParams
+{
+    /**
+     * @param string $commitTitle The title for the merge commit (optional)
+     * @param string $commitMessage The message body for the merge commit (optional)
+     * @param string $mergeMethod The merge method: 'merge', 'squash', or 'rebase' (optional, default: 'merge')
+     * @param string $sha The SHA that pull request head must match to allow merge (optional)
+     */
+    public function __construct(
+        public readonly string $commitTitle = '',
+        public readonly string $commitMessage = '',
+        public readonly string $mergeMethod = 'merge',
+        public readonly string $sha = ''
+    ) {}
+
+    /**
+     * Convert to array for API request, excluding empty fields
+     *
+     * @return array<string, string>
+     */
+    public function toArray(): array
+    {
+        $data = [];
+
+        if ($this->commitTitle !== '') {
+            $data['commit_title'] = $this->commitTitle;
+        }
+        if ($this->commitMessage !== '') {
+            $data['commit_message'] = $this->commitMessage;
+        }
+        if ($this->mergeMethod !== 'merge') {
+            $data['merge_method'] = $this->mergeMethod;
+        }
+        if ($this->sha !== '') {
+            $data['sha'] = $this->sha;
+        }
+
+        return $data;
+    }
+}
diff --git a/src/MergePullRequestRequestFactory.php b/src/MergePullRequestRequestFactory.php
new file mode 100644
index 0000000..be7d74a
--- /dev/null
+++ b/src/MergePullRequestRequestFactory.php
@@ -0,0 +1,59 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+
+/**
+ * Factory for creating requests to merge a pull request
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class MergePullRequestRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly StreamFactoryInterface $streamFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $pullNumber,
+        private readonly MergePullRequestParams $params
+    ) {}
+
+    /**
+     * Create HTTP request to merge a pull request
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/pulls/%d/merge',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->pullNumber
+        );
+
+        $jsonBody = json_encode($this->params->toArray(), JSON_THROW_ON_ERROR);
+        $stream = $this->streamFactory->createStream($jsonBody);
+
+        $request = $this->requestFactory->createRequest('PUT', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+        $request = $request->withHeader('Content-Type', 'application/json');
+        $request = $request->withBody($stream);
+
+        return $request;
+    }
+}
diff --git a/src/MergeResult.php b/src/MergeResult.php
new file mode 100644
index 0000000..cfcdf62
--- /dev/null
+++ b/src/MergeResult.php
@@ -0,0 +1,48 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Stringable;
+
+/**
+ * Represents the result of a pull request merge
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class MergeResult implements Stringable
+{
+    public function __construct(
+        public readonly string $sha,
+        public readonly bool $merged,
+        public readonly string $message
+    ) {}
+
+    public function __toString(): string
+    {
+        return $this->merged ? sprintf('Merged: %s (%s)', $this->message, $this->sha) : sprintf('Not merged: %s', $this->message);
+    }
+
+    /**
+     * Create from GitHub API response
+     *
+     * @param object $data The API response data
+     * @return self
+     */
+    public static function fromApiResponse(object $data): self
+    {
+        return new self(
+            sha: $data->sha ?? '',
+            merged: $data->merged ?? false,
+            message: $data->message ?? ''
+        );
+    }
+}
diff --git a/src/PullRequestUpdate.php b/src/PullRequestUpdate.php
new file mode 100644
index 0000000..890e02b
--- /dev/null
+++ b/src/PullRequestUpdate.php
@@ -0,0 +1,74 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+/**
+ * Data Transfer Object for pull request updates
+ *
+ * Copyright 2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class PullRequestUpdate
+{
+    /**
+     * @param ?string $title New PR title
+     * @param ?string $body New PR body/description
+     * @param ?string $base New base branch
+     * @param ?string $state New state (open or closed)
+     */
+    public function __construct(
+        public readonly ?string $title = null,
+        public readonly ?string $body = null,
+        public readonly ?string $base = null,
+        public readonly ?string $state = null
+    ) {}
+
+    /**
+     * Convert to array for JSON encoding (only includes set fields)
+     *
+     * @return array<string, string>
+     */
+    public function toArray(): array
+    {
+        $data = [];
+
+        if ($this->title !== null) {
+            $data['title'] = $this->title;
+        }
+
+        if ($this->body !== null) {
+            $data['body'] = $this->body;
+        }
+
+        if ($this->base !== null) {
+            $data['base'] = $this->base;
+        }
+
+        if ($this->state !== null) {
+            $data['state'] = $this->state;
+        }
+
+        return $data;
+    }
+
+    /**
+     * Check if any field is set
+     *
+     * @return bool True if at least one field is set
+     */
+    public function isEmpty(): bool
+    {
+        return $this->title === null
+            && $this->body === null
+            && $this->base === null
+            && $this->state === null;
+    }
+}
diff --git a/src/RemoveLabelRequestFactory.php b/src/RemoveLabelRequestFactory.php
new file mode 100644
index 0000000..0418a1a
--- /dev/null
+++ b/src/RemoveLabelRequestFactory.php
@@ -0,0 +1,53 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Factory for creating requests to remove a label from an issue/PR
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class RemoveLabelRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $issueNumber,
+        private readonly string $labelName
+    ) {}
+
+    /**
+     * Create HTTP request to remove a label
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/issues/%d/labels/%s',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->issueNumber,
+            urlencode($this->labelName)
+        );
+
+        $request = $this->requestFactory->createRequest('DELETE', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+
+        return $request;
+    }
+}
diff --git a/src/RequestReviewersRequestFactory.php b/src/RequestReviewersRequestFactory.php
new file mode 100644
index 0000000..7f0f6fa
--- /dev/null
+++ b/src/RequestReviewersRequestFactory.php
@@ -0,0 +1,72 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+
+/**
+ * Factory for creating requests to request reviewers for a pull request
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class RequestReviewersRequestFactory
+{
+    /**
+     * @param array<string> $reviewers User logins
+     * @param array<string> $teamReviewers Team slugs
+     */
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly StreamFactoryInterface $streamFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $pullNumber,
+        private readonly array $reviewers = [],
+        private readonly array $teamReviewers = []
+    ) {}
+
+    /**
+     * Create HTTP request to request reviewers
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/pulls/%d/requested_reviewers',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->pullNumber
+        );
+
+        $payload = [];
+        if (!empty($this->reviewers)) {
+            $payload['reviewers'] = $this->reviewers;
+        }
+        if (!empty($this->teamReviewers)) {
+            $payload['team_reviewers'] = $this->teamReviewers;
+        }
+
+        $jsonBody = json_encode($payload, JSON_THROW_ON_ERROR);
+        $stream = $this->streamFactory->createStream($jsonBody);
+
+        $request = $this->requestFactory->createRequest('POST', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+        $request = $request->withHeader('Content-Type', 'application/json');
+        $request = $request->withBody($stream);
+
+        return $request;
+    }
+}
diff --git a/src/SetLabelsRequestFactory.php b/src/SetLabelsRequestFactory.php
new file mode 100644
index 0000000..61cecbd
--- /dev/null
+++ b/src/SetLabelsRequestFactory.php
@@ -0,0 +1,62 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+
+/**
+ * Factory for creating requests to set (replace) all labels on an issue/PR
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class SetLabelsRequestFactory
+{
+    /**
+     * @param array<string> $labels Label names to set (replaces existing)
+     */
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly StreamFactoryInterface $streamFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $issueNumber,
+        private readonly array $labels
+    ) {}
+
+    /**
+     * Create HTTP request to set labels
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/issues/%d/labels',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->issueNumber
+        );
+
+        $jsonBody = json_encode(['labels' => $this->labels], JSON_THROW_ON_ERROR);
+        $stream = $this->streamFactory->createStream($jsonBody);
+
+        $request = $this->requestFactory->createRequest('PUT', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+        $request = $request->withHeader('Content-Type', 'application/json');
+        $request = $request->withBody($stream);
+
+        return $request;
+    }
+}
diff --git a/src/UpdateCommentRequestFactory.php b/src/UpdateCommentRequestFactory.php
new file mode 100644
index 0000000..a81f1e5
--- /dev/null
+++ b/src/UpdateCommentRequestFactory.php
@@ -0,0 +1,59 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+
+/**
+ * Factory for creating requests to update a comment
+ *
+ * Copyright 2026 The Horde Project (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class UpdateCommentRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly StreamFactoryInterface $streamFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $commentId,
+        private readonly string $body
+    ) {}
+
+    /**
+     * Create HTTP request to update a comment
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/issues/comments/%d',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->commentId
+        );
+
+        $jsonBody = json_encode(['body' => $this->body], JSON_THROW_ON_ERROR);
+        $stream = $this->streamFactory->createStream($jsonBody);
+
+        $request = $this->requestFactory->createRequest('PATCH', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+        $request = $request->withHeader('Content-Type', 'application/json');
+        $request = $request->withBody($stream);
+
+        return $request;
+    }
+}
diff --git a/src/UpdatePullRequestRequestFactory.php b/src/UpdatePullRequestRequestFactory.php
new file mode 100644
index 0000000..9730392
--- /dev/null
+++ b/src/UpdatePullRequestRequestFactory.php
@@ -0,0 +1,59 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient;
+
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+
+/**
+ * Factory for creating requests to update a pull request
+ *
+ * Copyright 2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category Horde
+ * @package  GithubApiClient
+ * @license  http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ */
+class UpdatePullRequestRequestFactory
+{
+    public function __construct(
+        private readonly RequestFactoryInterface $requestFactory,
+        private readonly StreamFactoryInterface $streamFactory,
+        private readonly GithubApiConfig $config,
+        private readonly GithubRepository $repo,
+        private readonly int $pullNumber,
+        private readonly PullRequestUpdate $update
+    ) {}
+
+    /**
+     * Create HTTP request to update a pull request
+     *
+     * @return RequestInterface
+     */
+    public function create(): RequestInterface
+    {
+        $url = sprintf(
+            'https://api.github.com/repos/%s/%s/pulls/%d',
+            $this->repo->owner,
+            $this->repo->name,
+            $this->pullNumber
+        );
+
+        $jsonBody = json_encode($this->update->toArray(), JSON_THROW_ON_ERROR);
+        $stream = $this->streamFactory->createStream($jsonBody);
+
+        $request = $this->requestFactory->createRequest('PATCH', $url);
+        $request = $request->withHeader('Authorization', 'token ' . $this->config->accessToken);
+        $request = $request->withHeader('Accept', 'application/vnd.github.v3+json');
+        $request = $request->withHeader('Content-Type', 'application/json');
+        $request = $request->withBody($stream);
+
+        return $request;
+    }
+}
diff --git a/test/unit/CreatePullRequestParamsTest.php b/test/unit/CreatePullRequestParamsTest.php
new file mode 100644
index 0000000..d300dbd
--- /dev/null
+++ b/test/unit/CreatePullRequestParamsTest.php
@@ -0,0 +1,189 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\CreatePullRequestParams;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(CreatePullRequestParams::class)]
+class CreatePullRequestParamsTest extends TestCase
+{
+    public function testConstructorWithRequiredParameters(): void
+    {
+        $params = new CreatePullRequestParams(
+            title: 'Add new feature',
+            head: 'feature-branch',
+            base: 'main'
+        );
+
+        $this->assertSame('Add new feature', $params->title);
+        $this->assertSame('feature-branch', $params->head);
+        $this->assertSame('main', $params->base);
+        $this->assertSame('', $params->body);
+        $this->assertFalse($params->draft);
+        $this->assertTrue($params->maintainerCanModify);
+    }
+
+    public function testConstructorWithAllParameters(): void
+    {
+        $params = new CreatePullRequestParams(
+            title: 'Fix bug in authentication',
+            head: 'fix/auth-bug',
+            base: 'develop',
+            body: 'This PR fixes the authentication bug\n\nCloses #123',
+            draft: true,
+            maintainerCanModify: false
+        );
+
+        $this->assertSame('Fix bug in authentication', $params->title);
+        $this->assertSame('fix/auth-bug', $params->head);
+        $this->assertSame('develop', $params->base);
+        $this->assertSame('This PR fixes the authentication bug\n\nCloses #123', $params->body);
+        $this->assertTrue($params->draft);
+        $this->assertFalse($params->maintainerCanModify);
+    }
+
+    public function testToArrayWithRequiredParametersOnly(): void
+    {
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'test',
+            base: 'main'
+        );
+
+        $array = $params->toArray();
+
+        $this->assertSame([
+            'title' => 'Test PR',
+            'head' => 'test',
+            'base' => 'main',
+            'maintainer_can_modify' => true
+        ], $array);
+    }
+
+    public function testToArrayWithAllParameters(): void
+    {
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'test',
+            base: 'main',
+            body: 'Test description',
+            draft: true,
+            maintainerCanModify: false
+        );
+
+        $array = $params->toArray();
+
+        $this->assertSame([
+            'title' => 'Test PR',
+            'head' => 'test',
+            'base' => 'main',
+            'maintainer_can_modify' => false,
+            'body' => 'Test description',
+            'draft' => true
+        ], $array);
+    }
+
+    public function testToArrayExcludesEmptyBody(): void
+    {
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'test',
+            base: 'main',
+            body: ''
+        );
+
+        $array = $params->toArray();
+
+        $this->assertArrayNotHasKey('body', $array);
+    }
+
+    public function testToArrayExcludesDraftWhenFalse(): void
+    {
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'test',
+            base: 'main',
+            draft: false
+        );
+
+        $array = $params->toArray();
+
+        $this->assertArrayNotHasKey('draft', $array);
+    }
+
+    public function testToArrayIncludesDraftWhenTrue(): void
+    {
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'test',
+            base: 'main',
+            draft: true
+        );
+
+        $array = $params->toArray();
+
+        $this->assertArrayHasKey('draft', $array);
+        $this->assertTrue($array['draft']);
+    }
+
+    public function testMaintainerCanModifyDefaultTrue(): void
+    {
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'test',
+            base: 'main'
+        );
+
+        $array = $params->toArray();
+
+        $this->assertTrue($array['maintainer_can_modify']);
+    }
+
+    public function testMaintainerCanModifyCanBeFalse(): void
+    {
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'test',
+            base: 'main',
+            maintainerCanModify: false
+        );
+
+        $array = $params->toArray();
+
+        $this->assertFalse($array['maintainer_can_modify']);
+    }
+
+    public function testHeadBranchFormats(): void
+    {
+        // Simple branch name
+        $params1 = new CreatePullRequestParams('Test', 'feature', 'main');
+        $this->assertSame('feature', $params1->head);
+
+        // Branch with owner prefix
+        $params2 = new CreatePullRequestParams('Test', 'username:feature', 'main');
+        $this->assertSame('username:feature', $params2->head);
+
+        // Branch with slashes
+        $params3 = new CreatePullRequestParams('Test', 'feature/add-auth', 'main');
+        $this->assertSame('feature/add-auth', $params3->head);
+    }
+
+    public function testBaseBranchFormats(): void
+    {
+        // main branch
+        $params1 = new CreatePullRequestParams('Test', 'feature', 'main');
+        $this->assertSame('main', $params1->base);
+
+        // develop branch
+        $params2 = new CreatePullRequestParams('Test', 'feature', 'develop');
+        $this->assertSame('develop', $params2->base);
+
+        // release branch
+        $params3 = new CreatePullRequestParams('Test', 'hotfix', 'release/1.0');
+        $this->assertSame('release/1.0', $params3->base);
+    }
+}
diff --git a/test/unit/GithubApiClientErrorHandlingTest.php b/test/unit/GithubApiClientErrorHandlingTest.php
new file mode 100644
index 0000000..544e353
--- /dev/null
+++ b/test/unit/GithubApiClientErrorHandlingTest.php
@@ -0,0 +1,171 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\CreatePullRequestParams;
+use Horde\GithubApiClient\GithubApiClient;
+use Horde\GithubApiClient\GithubApiConfig;
+use Horde\GithubApiClient\GithubRepository;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use Psr\Http\Client\ClientInterface;
+use Psr\Http\Message\RequestFactoryInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\StreamInterface;
+use Psr\Http\Message\StreamFactoryInterface;
+
+#[CoversClass(GithubApiClient::class)]
+class GithubApiClientErrorHandlingTest extends TestCase
+{
+    public function testCreatePullRequestThrowsOn422UnprocessableEntity(): void
+    {
+        // This test covers the case where:
+        // - The branch doesn't exist on remote
+        // - The PR already exists
+        // - There are validation errors in the request
+
+        $httpClient = $this->createMock(ClientInterface::class);
+        $requestFactory = $this->createMock(RequestFactoryInterface::class);
+        $streamFactory = $this->createMock(StreamFactoryInterface::class);
+        $config = new GithubApiConfig(accessToken: 'test-token');
+
+        $request = $this->createMock(RequestInterface::class);
+        $stream = $this->createMock(StreamInterface::class);
+        $response = $this->createMock(ResponseInterface::class);
+
+        // Mock the request creation chain
+        $requestFactory->method('createRequest')->willReturn($request);
+        $request->method('withHeader')->willReturnSelf();
+        $request->method('withBody')->willReturnSelf();
+        $streamFactory->method('createStream')->willReturn($stream);
+
+        // Mock 422 Unprocessable Entity response
+        $response->method('getStatusCode')->willReturn(422);
+        $response->method('getReasonPhrase')->willReturn('Unprocessable Entity');
+        $httpClient->method('sendRequest')->willReturn($response);
+
+        $client = new GithubApiClient($httpClient, $requestFactory, $config, $streamFactory);
+        $repo = GithubRepository::fromFullName('horde/githubapiclient');
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'non-existent-branch',
+            base: 'main'
+        );
+
+        $this->expectException(\Exception::class);
+        $this->expectExceptionMessage('422 Unprocessable Entity');
+
+        $client->createPullRequest($repo, $params);
+    }
+
+    public function testCreatePullRequestThrowsOn404NotFound(): void
+    {
+        // This test covers the case where the repository doesn't exist
+
+        $httpClient = $this->createMock(ClientInterface::class);
+        $requestFactory = $this->createMock(RequestFactoryInterface::class);
+        $streamFactory = $this->createMock(StreamFactoryInterface::class);
+        $config = new GithubApiConfig(accessToken: 'test-token');
+
+        $request = $this->createMock(RequestInterface::class);
+        $stream = $this->createMock(StreamInterface::class);
+        $response = $this->createMock(ResponseInterface::class);
+
+        $requestFactory->method('createRequest')->willReturn($request);
+        $request->method('withHeader')->willReturnSelf();
+        $request->method('withBody')->willReturnSelf();
+        $streamFactory->method('createStream')->willReturn($stream);
+
+        $response->method('getStatusCode')->willReturn(404);
+        $response->method('getReasonPhrase')->willReturn('Not Found');
+        $httpClient->method('sendRequest')->willReturn($response);
+
+        $client = new GithubApiClient($httpClient, $requestFactory, $config, $streamFactory);
+        $repo = GithubRepository::fromFullName('nonexistent/repo');
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'feature',
+            base: 'main'
+        );
+
+        $this->expectException(\Exception::class);
+        $this->expectExceptionMessage('404 Not Found');
+
+        $client->createPullRequest($repo, $params);
+    }
+
+    public function testCreatePullRequestThrowsOn401Unauthorized(): void
+    {
+        // This test covers the case where the token is invalid or expired
+
+        $httpClient = $this->createMock(ClientInterface::class);
+        $requestFactory = $this->createMock(RequestFactoryInterface::class);
+        $streamFactory = $this->createMock(StreamFactoryInterface::class);
+        $config = new GithubApiConfig(accessToken: 'invalid-token');
+
+        $request = $this->createMock(RequestInterface::class);
+        $stream = $this->createMock(StreamInterface::class);
+        $response = $this->createMock(ResponseInterface::class);
+
+        $requestFactory->method('createRequest')->willReturn($request);
+        $request->method('withHeader')->willReturnSelf();
+        $request->method('withBody')->willReturnSelf();
+        $streamFactory->method('createStream')->willReturn($stream);
+
+        $response->method('getStatusCode')->willReturn(401);
+        $response->method('getReasonPhrase')->willReturn('Unauthorized');
+        $httpClient->method('sendRequest')->willReturn($response);
+
+        $client = new GithubApiClient($httpClient, $requestFactory, $config, $streamFactory);
+        $repo = GithubRepository::fromFullName('horde/githubapiclient');
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'feature',
+            base: 'main'
+        );
+
+        $this->expectException(\Exception::class);
+        $this->expectExceptionMessage('401 Unauthorized');
+
+        $client->createPullRequest($repo, $params);
+    }
+
+    public function testCreatePullRequestThrowsOn403Forbidden(): void
+    {
+        // This test covers the case where the token lacks necessary permissions
+
+        $httpClient = $this->createMock(ClientInterface::class);
+        $requestFactory = $this->createMock(RequestFactoryInterface::class);
+        $streamFactory = $this->createMock(StreamFactoryInterface::class);
+        $config = new GithubApiConfig(accessToken: 'test-token');
+
+        $request = $this->createMock(RequestInterface::class);
+        $stream = $this->createMock(StreamInterface::class);
+        $response = $this->createMock(ResponseInterface::class);
+
+        $requestFactory->method('createRequest')->willReturn($request);
+        $request->method('withHeader')->willReturnSelf();
+        $request->method('withBody')->willReturnSelf();
+        $streamFactory->method('createStream')->willReturn($stream);
+
+        $response->method('getStatusCode')->willReturn(403);
+        $response->method('getReasonPhrase')->willReturn('Forbidden');
+        $httpClient->method('sendRequest')->willReturn($response);
+
+        $client = new GithubApiClient($httpClient, $requestFactory, $config, $streamFactory);
+        $repo = GithubRepository::fromFullName('horde/githubapiclient');
+        $params = new CreatePullRequestParams(
+            title: 'Test PR',
+            head: 'feature',
+            base: 'main'
+        );
+
+        $this->expectException(\Exception::class);
+        $this->expectExceptionMessage('403 Forbidden');
+
+        $client->createPullRequest($repo, $params);
+    }
+}
diff --git a/test/unit/GithubCheckRunTest.php b/test/unit/GithubCheckRunTest.php
new file mode 100644
index 0000000..6dae89f
--- /dev/null
+++ b/test/unit/GithubCheckRunTest.php
@@ -0,0 +1,145 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\GithubCheckRun;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(GithubCheckRun::class)]
+class GithubCheckRunTest extends TestCase
+{
+    public function testConstructorWithAllParameters(): void
+    {
+        $checkRun = new GithubCheckRun(
+            id: 123456,
+            name: 'Build and Test',
+            status: 'completed',
+            conclusion: 'success',
+            headSha: 'abc123def456',
+            htmlUrl: 'https://github.com/owner/repo/runs/123456',
+            detailsUrl: 'https://github.com/owner/repo/runs/123456/details',
+            startedAt: '2026-02-26T10:00:00Z',
+            completedAt: '2026-02-26T10:05:00Z'
+        );
+
+        $this->assertSame(123456, $checkRun->id);
+        $this->assertSame('Build and Test', $checkRun->name);
+        $this->assertSame('completed', $checkRun->status);
+        $this->assertSame('success', $checkRun->conclusion);
+        $this->assertSame('abc123def456', $checkRun->headSha);
+        $this->assertSame('https://github.com/owner/repo/runs/123456', $checkRun->htmlUrl);
+        $this->assertSame('https://github.com/owner/repo/runs/123456/details', $checkRun->detailsUrl);
+        $this->assertSame('2026-02-26T10:00:00Z', $checkRun->startedAt);
+        $this->assertSame('2026-02-26T10:05:00Z', $checkRun->completedAt);
+    }
+
+    public function testToString(): void
+    {
+        $checkRun = new GithubCheckRun(
+            id: 789,
+            name: 'Lint',
+            status: 'completed',
+            conclusion: 'failure',
+            headSha: 'def789',
+            htmlUrl: '',
+            detailsUrl: '',
+            startedAt: '',
+            completedAt: ''
+        );
+
+        $this->assertSame('Lint: completed/failure', (string) $checkRun);
+    }
+
+    public function testFromApiResponseWithCompleteData(): void
+    {
+        $data = (object) [
+            'id' => 999888,
+            'name' => 'CodeQL Analysis',
+            'status' => 'in_progress',
+            'conclusion' => null,
+            'head_sha' => 'ghi789jkl012',
+            'html_url' => 'https://github.com/org/repo/runs/999888',
+            'details_url' => 'https://github.com/org/repo/runs/999888/details',
+            'started_at' => '2026-02-26T11:00:00Z',
+            'completed_at' => null
+        ];
+
+        $checkRun = GithubCheckRun::fromApiResponse($data);
+
+        $this->assertSame(999888, $checkRun->id);
+        $this->assertSame('CodeQL Analysis', $checkRun->name);
+        $this->assertSame('in_progress', $checkRun->status);
+        $this->assertSame('', $checkRun->conclusion);
+        $this->assertSame('ghi789jkl012', $checkRun->headSha);
+        $this->assertSame('https://github.com/org/repo/runs/999888', $checkRun->htmlUrl);
+        $this->assertSame('https://github.com/org/repo/runs/999888/details', $checkRun->detailsUrl);
+        $this->assertSame('2026-02-26T11:00:00Z', $checkRun->startedAt);
+        $this->assertSame('', $checkRun->completedAt);
+    }
+
+    public function testFromApiResponseWithMinimalData(): void
+    {
+        $data = (object) [];
+
+        $checkRun = GithubCheckRun::fromApiResponse($data);
+
+        $this->assertSame(0, $checkRun->id);
+        $this->assertSame('', $checkRun->name);
+        $this->assertSame('', $checkRun->status);
+        $this->assertSame('', $checkRun->conclusion);
+        $this->assertSame('', $checkRun->headSha);
+        $this->assertSame('', $checkRun->htmlUrl);
+        $this->assertSame('', $checkRun->detailsUrl);
+        $this->assertSame('', $checkRun->startedAt);
+        $this->assertSame('', $checkRun->completedAt);
+    }
+
+    public function testCheckRunStatuses(): void
+    {
+        // queued
+        $queuedRun = new GithubCheckRun(1, 'Test', 'queued', '', '', '', '', '', '');
+        $this->assertSame('queued', $queuedRun->status);
+
+        // in_progress
+        $inProgressRun = new GithubCheckRun(2, 'Test', 'in_progress', '', '', '', '', '', '');
+        $this->assertSame('in_progress', $inProgressRun->status);
+
+        // completed
+        $completedRun = new GithubCheckRun(3, 'Test', 'completed', '', '', '', '', '', '');
+        $this->assertSame('completed', $completedRun->status);
+    }
+
+    public function testCheckRunConclusions(): void
+    {
+        // success
+        $successRun = new GithubCheckRun(1, 'Test', 'completed', 'success', '', '', '', '', '');
+        $this->assertSame('success', $successRun->conclusion);
+
+        // failure
+        $failureRun = new GithubCheckRun(2, 'Test', 'completed', 'failure', '', '', '', '', '');
+        $this->assertSame('failure', $failureRun->conclusion);
+
+        // neutral
+        $neutralRun = new GithubCheckRun(3, 'Test', 'completed', 'neutral', '', '', '', '', '');
+        $this->assertSame('neutral', $neutralRun->conclusion);
+
+        // cancelled
+        $cancelledRun = new GithubCheckRun(4, 'Test', 'completed', 'cancelled', '', '', '', '', '');
+        $this->assertSame('cancelled', $cancelledRun->conclusion);
+
+        // skipped
+        $skippedRun = new GithubCheckRun(5, 'Test', 'completed', 'skipped', '', '', '', '', '');
+        $this->assertSame('skipped', $skippedRun->conclusion);
+
+        // timed_out
+        $timedOutRun = new GithubCheckRun(6, 'Test', 'completed', 'timed_out', '', '', '', '', '');
+        $this->assertSame('timed_out', $timedOutRun->conclusion);
+
+        // action_required
+        $actionRequiredRun = new GithubCheckRun(7, 'Test', 'completed', 'action_required', '', '', '', '', '');
+        $this->assertSame('action_required', $actionRequiredRun->conclusion);
+    }
+}
diff --git a/test/unit/GithubCommentTest.php b/test/unit/GithubCommentTest.php
new file mode 100644
index 0000000..0e2ab0a
--- /dev/null
+++ b/test/unit/GithubCommentTest.php
@@ -0,0 +1,110 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\GithubComment;
+use Horde\GithubApiClient\GithubUser;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(GithubComment::class)]
+class GithubCommentTest extends TestCase
+{
+    public function testConstructorWithAllParameters(): void
+    {
+        $author = new GithubUser(
+            login: 'testuser',
+            id: 123,
+            avatarUrl: 'https://avatar.example.com/test.png',
+            htmlUrl: 'https://github.com/testuser'
+        );
+
+        $comment = new GithubComment(
+            id: 456789,
+            body: 'This is a test comment',
+            author: $author,
+            createdAt: '2026-02-26T10:00:00Z',
+            updatedAt: '2026-02-26T11:00:00Z',
+            htmlUrl: 'https://github.com/owner/repo/pull/1#issuecomment-456789',
+            apiUrl: 'https://api.github.com/repos/owner/repo/issues/comments/456789'
+        );
+
+        $this->assertSame(456789, $comment->id);
+        $this->assertSame('This is a test comment', $comment->body);
+        $this->assertSame($author, $comment->author);
+        $this->assertSame('2026-02-26T10:00:00Z', $comment->createdAt);
+        $this->assertSame('2026-02-26T11:00:00Z', $comment->updatedAt);
+        $this->assertSame('https://github.com/owner/repo/pull/1#issuecomment-456789', $comment->htmlUrl);
+        $this->assertSame('https://api.github.com/repos/owner/repo/issues/comments/456789', $comment->apiUrl);
+    }
+
+    public function testToStringReturnsHtmlUrl(): void
+    {
+        $author = new GithubUser(
+            login: 'testuser',
+            id: 123,
+            avatarUrl: 'https://avatar.example.com/test.png',
+            htmlUrl: 'https://github.com/testuser'
+        );
+
+        $comment = new GithubComment(
+            id: 456789,
+            body: 'Test',
+            author: $author,
+            createdAt: '2026-02-26T10:00:00Z',
+            updatedAt: '2026-02-26T10:00:00Z',
+            htmlUrl: 'https://github.com/owner/repo/pull/1#issuecomment-456789',
+            apiUrl: 'https://api.github.com/repos/owner/repo/issues/comments/456789'
+        );
+
+        $this->assertSame('https://github.com/owner/repo/pull/1#issuecomment-456789', (string) $comment);
+    }
+
+    public function testFromApiResponseWithCompleteData(): void
+    {
+        $data = (object) [
+            'id' => 999888,
+            'body' => 'API comment body',
+            'user' => (object) [
+                'login' => 'apiuser',
+                'id' => 777,
+                'avatar_url' => 'https://avatar.example.com/api.png',
+                'html_url' => 'https://github.com/apiuser',
+                'type' => 'User'
+            ],
+            'created_at' => '2026-01-15T08:30:00Z',
+            'updated_at' => '2026-01-15T09:45:00Z',
+            'html_url' => 'https://github.com/org/repo/pull/5#issuecomment-999888',
+            'url' => 'https://api.github.com/repos/org/repo/issues/comments/999888'
+        ];
+
+        $comment = GithubComment::fromApiResponse($data);
+
+        $this->assertSame(999888, $comment->id);
+        $this->assertSame('API comment body', $comment->body);
+        $this->assertSame('apiuser', $comment->author->login);
+        $this->assertSame('2026-01-15T08:30:00Z', $comment->createdAt);
+        $this->assertSame('2026-01-15T09:45:00Z', $comment->updatedAt);
+        $this->assertSame('https://github.com/org/repo/pull/5#issuecomment-999888', $comment->htmlUrl);
+        $this->assertSame('https://api.github.com/repos/org/repo/issues/comments/999888', $comment->apiUrl);
+    }
+
+    public function testFromApiResponseWithMinimalData(): void
+    {
+        $data = (object) [
+            'user' => (object) []
+        ];
+
+        $comment = GithubComment::fromApiResponse($data);
+
+        $this->assertSame(0, $comment->id);
+        $this->assertSame('', $comment->body);
+        $this->assertSame('', $comment->author->login);
+        $this->assertSame('', $comment->createdAt);
+        $this->assertSame('', $comment->updatedAt);
+        $this->assertSame('', $comment->htmlUrl);
+        $this->assertSame('', $comment->apiUrl);
+    }
+}
diff --git a/test/unit/GithubLabelTest.php b/test/unit/GithubLabelTest.php
new file mode 100644
index 0000000..8fe3dcb
--- /dev/null
+++ b/test/unit/GithubLabelTest.php
@@ -0,0 +1,88 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\GithubLabel;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(GithubLabel::class)]
+class GithubLabelTest extends TestCase
+{
+    public function testConstructorWithDescription(): void
+    {
+        $label = new GithubLabel(
+            name: 'bug',
+            color: 'd73a4a',
+            description: 'Something isn\'t working'
+        );
+
+        $this->assertSame('bug', $label->name);
+        $this->assertSame('d73a4a', $label->color);
+        $this->assertSame('Something isn\'t working', $label->description);
+    }
+
+    public function testConstructorWithoutDescription(): void
+    {
+        $label = new GithubLabel(
+            name: 'enhancement',
+            color: 'a2eeef'
+        );
+
+        $this->assertSame('enhancement', $label->name);
+        $this->assertSame('a2eeef', $label->color);
+        $this->assertNull($label->description);
+    }
+
+    public function testToStringReturnsName(): void
+    {
+        $label = new GithubLabel(
+            name: 'feature',
+            color: '0052cc'
+        );
+
+        $this->assertSame('feature', (string) $label);
+    }
+
+    public function testFromApiResponseWithCompleteData(): void
+    {
+        $data = (object) [
+            'name' => 'documentation',
+            'color' => '0075ca',
+            'description' => 'Improvements or additions to documentation'
+        ];
+
+        $label = GithubLabel::fromApiResponse($data);
+
+        $this->assertSame('documentation', $label->name);
+        $this->assertSame('0075ca', $label->color);
+        $this->assertSame('Improvements or additions to documentation', $label->description);
+    }
+
+    public function testFromApiResponseWithoutDescription(): void
+    {
+        $data = (object) [
+            'name' => 'wontfix',
+            'color' => 'ffffff'
+        ];
+
+        $label = GithubLabel::fromApiResponse($data);
+
+        $this->assertSame('wontfix', $label->name);
+        $this->assertSame('ffffff', $label->color);
+        $this->assertNull($label->description);
+    }
+
+    public function testFromApiResponseWithMinimalData(): void
+    {
+        $data = (object) [];
+
+        $label = GithubLabel::fromApiResponse($data);
+
+        $this->assertSame('', $label->name);
+        $this->assertSame('000000', $label->color);
+        $this->assertNull($label->description);
+    }
+}
diff --git a/test/unit/GithubRepositoryTest.php b/test/unit/GithubRepositoryTest.php
new file mode 100644
index 0000000..ff4fde9
--- /dev/null
+++ b/test/unit/GithubRepositoryTest.php
@@ -0,0 +1,119 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\GithubRepository;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(GithubRepository::class)]
+class GithubRepositoryTest extends TestCase
+{
+    public function testFromFullNameParsesOwnerAndName(): void
+    {
+        $repo = GithubRepository::fromFullName('horde/githubapiclient');
+
+        $this->assertSame('horde', $repo->owner);
+        $this->assertSame('githubapiclient', $repo->name);
+        $this->assertSame('horde/githubapiclient', $repo->getFullName());
+    }
+
+    public function testFromFullNameWithDifferentOwner(): void
+    {
+        $repo = GithubRepository::fromFullName('octocat/Hello-World');
+
+        $this->assertSame('octocat', $repo->owner);
+        $this->assertSame('Hello-World', $repo->name);
+        $this->assertSame('octocat/Hello-World', $repo->getFullName());
+    }
+
+    public function testFromFullNameWithHyphenatedNames(): void
+    {
+        $repo = GithubRepository::fromFullName('my-org/my-repo-name');
+
+        $this->assertSame('my-org', $repo->owner);
+        $this->assertSame('my-repo-name', $repo->name);
+        $this->assertSame('my-org/my-repo-name', $repo->getFullName());
+    }
+
+    public function testFromFullNameThrowsOnEmptyString(): void
+    {
+        $this->expectException(\InvalidArgumentException::class);
+        $this->expectExceptionMessage('Full name cannot be empty');
+
+        GithubRepository::fromFullName('');
+    }
+
+    public function testFromFullNameThrowsOnInvalidFormat(): void
+    {
+        $this->expectException(\InvalidArgumentException::class);
+        $this->expectExceptionMessage('Invalid full name format');
+
+        GithubRepository::fromFullName('invalid-no-slash');
+    }
+
+    public function testFromFullNameThrowsOnTooManySlashes(): void
+    {
+        $this->expectException(\InvalidArgumentException::class);
+        $this->expectExceptionMessage('Invalid full name format');
+
+        GithubRepository::fromFullName('owner/repo/extra');
+    }
+
+    public function testFromApiArrayParsesOwnerFromFullName(): void
+    {
+        $data = [
+            'name' => 'components',
+            'full_name' => 'horde/components',
+            'description' => 'Component management tool',
+            'clone_url' => 'https://github.com/horde/components.git'
+        ];
+
+        $repo = GithubRepository::fromApiArray($data);
+
+        $this->assertSame('horde', $repo->owner);
+        $this->assertSame('components', $repo->name);
+        $this->assertSame('horde/components', $repo->getFullName());
+        $this->assertSame('Component management tool', $repo->getDescription());
+    }
+
+    public function testConstructorParsesOwnerFromFullName(): void
+    {
+        $repo = new GithubRepository(
+            name: 'test-repo',
+            fullName: 'test-owner/test-repo',
+            description: 'Test',
+            cloneUrl: 'https://github.com/test-owner/test-repo.git'
+        );
+
+        $this->assertSame('test-owner', $repo->owner);
+        $this->assertSame('test-repo', $repo->name);
+    }
+
+    public function testOwnerAndNameArePubliclyAccessible(): void
+    {
+        $repo = GithubRepository::fromFullName('microsoft/vscode');
+
+        // Test that owner and name can be accessed as public properties
+        // This is required for request factories to build API URLs
+        $owner = $repo->owner;
+        $name = $repo->name;
+
+        $this->assertSame('microsoft', $owner);
+        $this->assertSame('vscode', $name);
+    }
+
+    public function testOwnerAndNameAreReadonly(): void
+    {
+        $repo = GithubRepository::fromFullName('github/gitignore');
+
+        // Verify properties are readonly (this will be caught by PHP at runtime)
+        $reflection = new \ReflectionProperty(GithubRepository::class, 'owner');
+        $this->assertTrue($reflection->isReadOnly());
+
+        $reflection = new \ReflectionProperty(GithubRepository::class, 'name');
+        $this->assertTrue($reflection->isReadOnly());
+    }
+}
diff --git a/test/unit/GithubReviewTest.php b/test/unit/GithubReviewTest.php
new file mode 100644
index 0000000..ca1940f
--- /dev/null
+++ b/test/unit/GithubReviewTest.php
@@ -0,0 +1,133 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\GithubReview;
+use Horde\GithubApiClient\GithubUser;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(GithubReview::class)]
+class GithubReviewTest extends TestCase
+{
+    public function testConstructorWithAllParameters(): void
+    {
+        $user = new GithubUser(
+            login: 'reviewer',
+            id: 456,
+            avatarUrl: 'https://avatar.example.com/reviewer.png',
+            htmlUrl: 'https://github.com/reviewer',
+            type: 'User'
+        );
+
+        $review = new GithubReview(
+            id: 789123,
+            user: $user,
+            body: 'Looks good to me',
+            state: 'APPROVED',
+            htmlUrl: 'https://github.com/owner/repo/pull/1#pullrequestreview-789123',
+            submittedAt: '2026-02-26T12:00:00Z',
+            commitId: 'abc123def456'
+        );
+
+        $this->assertSame(789123, $review->id);
+        $this->assertSame($user, $review->user);
+        $this->assertSame('Looks good to me', $review->body);
+        $this->assertSame('APPROVED', $review->state);
+        $this->assertSame('https://github.com/owner/repo/pull/1#pullrequestreview-789123', $review->htmlUrl);
+        $this->assertSame('2026-02-26T12:00:00Z', $review->submittedAt);
+        $this->assertSame('abc123def456', $review->commitId);
+    }
+
+    public function testToStringReturnsHtmlUrl(): void
+    {
+        $user = new GithubUser(
+            login: 'reviewer',
+            id: 456,
+            avatarUrl: 'https://avatar.example.com/reviewer.png',
+            htmlUrl: 'https://github.com/reviewer',
+            type: 'User'
+        );
+
+        $review = new GithubReview(
+            id: 789123,
+            user: $user,
+            body: 'Test',
+            state: 'APPROVED',
+            htmlUrl: 'https://github.com/owner/repo/pull/1#pullrequestreview-789123',
+            submittedAt: '2026-02-26T12:00:00Z',
+            commitId: 'abc123'
+        );
+
+        $this->assertSame('https://github.com/owner/repo/pull/1#pullrequestreview-789123', (string) $review);
+    }
+
+    public function testFromApiResponseWithCompleteData(): void
+    {
+        $data = (object) [
+            'id' => 111222,
+            'user' => (object) [
+                'login' => 'apireviewer',
+                'id' => 333,
+                'avatar_url' => 'https://avatar.example.com/apireviewer.png',
+                'html_url' => 'https://github.com/apireviewer',
+                'type' => 'User'
+            ],
+            'body' => 'API review comment',
+            'state' => 'CHANGES_REQUESTED',
+            'html_url' => 'https://github.com/org/repo/pull/5#pullrequestreview-111222',
+            'submitted_at' => '2026-02-15T14:30:00Z',
+            'commit_id' => 'def789ghi012'
+        ];
+
+        $review = GithubReview::fromApiResponse($data);
+
+        $this->assertSame(111222, $review->id);
+        $this->assertSame('apireviewer', $review->user->login);
+        $this->assertSame('API review comment', $review->body);
+        $this->assertSame('CHANGES_REQUESTED', $review->state);
+        $this->assertSame('https://github.com/org/repo/pull/5#pullrequestreview-111222', $review->htmlUrl);
+        $this->assertSame('2026-02-15T14:30:00Z', $review->submittedAt);
+        $this->assertSame('def789ghi012', $review->commitId);
+    }
+
+    public function testFromApiResponseWithMinimalData(): void
+    {
+        $data = (object) [
+            'user' => (object) []
+        ];
+
+        $review = GithubReview::fromApiResponse($data);
+
+        $this->assertSame(0, $review->id);
+        $this->assertSame('', $review->user->login);
+        $this->assertSame('', $review->body);
+        $this->assertSame('', $review->state);
+        $this->assertSame('', $review->htmlUrl);
+        $this->assertSame('', $review->submittedAt);
+        $this->assertSame('', $review->commitId);
+    }
+
+    public function testReviewStates(): void
+    {
+        $user = new GithubUser('reviewer', 123, '', '', 'User');
+
+        // Test APPROVED state
+        $approvedReview = new GithubReview(1, $user, 'LGTM', 'APPROVED', '', '', '');
+        $this->assertSame('APPROVED', $approvedReview->state);
+
+        // Test CHANGES_REQUESTED state
+        $changesReview = new GithubReview(2, $user, 'Needs work', 'CHANGES_REQUESTED', '', '', '');
+        $this->assertSame('CHANGES_REQUESTED', $changesReview->state);
+
+        // Test COMMENTED state
+        $commentedReview = new GithubReview(3, $user, 'Some thoughts', 'COMMENTED', '', '', '');
+        $this->assertSame('COMMENTED', $commentedReview->state);
+
+        // Test DISMISSED state
+        $dismissedReview = new GithubReview(4, $user, 'Old review', 'DISMISSED', '', '', '');
+        $this->assertSame('DISMISSED', $dismissedReview->state);
+    }
+}
diff --git a/test/unit/GithubStatusTest.php b/test/unit/GithubStatusTest.php
new file mode 100644
index 0000000..b66c214
--- /dev/null
+++ b/test/unit/GithubStatusTest.php
@@ -0,0 +1,175 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\GithubCommitStatus;
+use Horde\GithubApiClient\GithubCombinedStatus;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(GithubCommitStatus::class)]
+#[CoversClass(GithubCombinedStatus::class)]
+class GithubStatusTest extends TestCase
+{
+    public function testCommitStatusConstructor(): void
+    {
+        $status = new GithubCommitStatus(
+            state: 'success',
+            context: 'continuous-integration/travis-ci',
+            description: 'The Travis CI build passed',
+            targetUrl: 'https://travis-ci.com/owner/repo/builds/12345',
+            createdAt: '2026-02-26T10:00:00Z',
+            updatedAt: '2026-02-26T10:05:00Z'
+        );
+
+        $this->assertSame('success', $status->state);
+        $this->assertSame('continuous-integration/travis-ci', $status->context);
+        $this->assertSame('The Travis CI build passed', $status->description);
+        $this->assertSame('https://travis-ci.com/owner/repo/builds/12345', $status->targetUrl);
+        $this->assertSame('2026-02-26T10:00:00Z', $status->createdAt);
+        $this->assertSame('2026-02-26T10:05:00Z', $status->updatedAt);
+    }
+
+    public function testCommitStatusToString(): void
+    {
+        $status = new GithubCommitStatus(
+            state: 'failure',
+            context: 'test/unit',
+            description: 'Tests failed',
+            targetUrl: '',
+            createdAt: '',
+            updatedAt: ''
+        );
+
+        $this->assertSame('test/unit: failure (Tests failed)', (string) $status);
+    }
+
+    public function testCommitStatusFromApiResponse(): void
+    {
+        $data = (object) [
+            'state' => 'pending',
+            'context' => 'test/integration',
+            'description' => 'Running integration tests',
+            'target_url' => 'https://ci.example.com/build/789',
+            'created_at' => '2026-02-26T11:00:00Z',
+            'updated_at' => '2026-02-26T11:01:00Z'
+        ];
+
+        $status = GithubCommitStatus::fromApiResponse($data);
+
+        $this->assertSame('pending', $status->state);
+        $this->assertSame('test/integration', $status->context);
+        $this->assertSame('Running integration tests', $status->description);
+        $this->assertSame('https://ci.example.com/build/789', $status->targetUrl);
+        $this->assertSame('2026-02-26T11:00:00Z', $status->createdAt);
+        $this->assertSame('2026-02-26T11:01:00Z', $status->updatedAt);
+    }
+
+    public function testCommitStatusFromApiResponseWithMinimalData(): void
+    {
+        $data = (object) [];
+
+        $status = GithubCommitStatus::fromApiResponse($data);
+
+        $this->assertSame('', $status->state);
+        $this->assertSame('', $status->context);
+        $this->assertSame('', $status->description);
+        $this->assertSame('', $status->targetUrl);
+        $this->assertSame('', $status->createdAt);
+        $this->assertSame('', $status->updatedAt);
+    }
+
+    public function testCombinedStatusConstructor(): void
+    {
+        $status1 = new GithubCommitStatus('success', 'ci/travis', 'Passed', '', '', '');
+        $status2 = new GithubCommitStatus('success', 'ci/github-actions', 'Passed', '', '', '');
+
+        $combined = new GithubCombinedStatus(
+            state: 'success',
+            sha: 'abc123def456',
+            totalCount: 2,
+            statuses: [$status1, $status2]
+        );
+
+        $this->assertSame('success', $combined->state);
+        $this->assertSame('abc123def456', $combined->sha);
+        $this->assertSame(2, $combined->totalCount);
+        $this->assertCount(2, $combined->statuses);
+        $this->assertSame($status1, $combined->statuses[0]);
+        $this->assertSame($status2, $combined->statuses[1]);
+    }
+
+    public function testCombinedStatusToString(): void
+    {
+        $combined = new GithubCombinedStatus(
+            state: 'pending',
+            sha: 'abc123',
+            totalCount: 3,
+            statuses: []
+        );
+
+        $this->assertSame('pending (3 checks)', (string) $combined);
+    }
+
+    public function testCombinedStatusFromApiResponse(): void
+    {
+        $data = (object) [
+            'state' => 'success',
+            'sha' => 'def789ghi012',
+            'total_count' => 2,
+            'statuses' => [
+                (object) [
+                    'state' => 'success',
+                    'context' => 'test1',
+                    'description' => 'Test 1 passed',
+                    'target_url' => 'https://ci.example.com/1',
+                    'created_at' => '2026-02-26T12:00:00Z',
+                    'updated_at' => '2026-02-26T12:01:00Z'
+                ],
+                (object) [
+                    'state' => 'success',
+                    'context' => 'test2',
+                    'description' => 'Test 2 passed',
+                    'target_url' => 'https://ci.example.com/2',
+                    'created_at' => '2026-02-26T12:00:00Z',
+                    'updated_at' => '2026-02-26T12:02:00Z'
+                ]
+            ]
+        ];
+
+        $combined = GithubCombinedStatus::fromApiResponse($data);
+
+        $this->assertSame('success', $combined->state);
+        $this->assertSame('def789ghi012', $combined->sha);
+        $this->assertSame(2, $combined->totalCount);
+        $this->assertCount(2, $combined->statuses);
+        $this->assertSame('test1', $combined->statuses[0]->context);
+        $this->assertSame('test2', $combined->statuses[1]->context);
+    }
+
+    public function testCombinedStatusFromApiResponseWithMinimalData(): void
+    {
+        $data = (object) [];
+
+        $combined = GithubCombinedStatus::fromApiResponse($data);
+
+        $this->assertSame('', $combined->state);
+        $this->assertSame('', $combined->sha);
+        $this->assertSame(0, $combined->totalCount);
+        $this->assertCount(0, $combined->statuses);
+    }
+
+    public function testCombinedStatusStates(): void
+    {
+        $successCombined = new GithubCombinedStatus('success', 'abc123', 1, []);
+        $this->assertSame('success', $successCombined->state);
+
+        $failureCombined = new GithubCombinedStatus('failure', 'def456', 1, []);
+        $this->assertSame('failure', $failureCombined->state);
+
+        $pendingCombined = new GithubCombinedStatus('pending', 'ghi789', 1, []);
+        $this->assertSame('pending', $pendingCombined->state);
+    }
+}
diff --git a/test/unit/GithubUserTest.php b/test/unit/GithubUserTest.php
new file mode 100644
index 0000000..af85068
--- /dev/null
+++ b/test/unit/GithubUserTest.php
@@ -0,0 +1,102 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\GithubUser;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(GithubUser::class)]
+class GithubUserTest extends TestCase
+{
+    public function testConstructorWithAllParameters(): void
+    {
+        $user = new GithubUser(
+            login: 'testuser',
+            id: 12345,
+            avatarUrl: 'https://avatar.example.com/testuser.png',
+            htmlUrl: 'https://github.com/testuser',
+            type: 'User'
+        );
+
+        $this->assertSame('testuser', $user->login);
+        $this->assertSame(12345, $user->id);
+        $this->assertSame('https://avatar.example.com/testuser.png', $user->avatarUrl);
+        $this->assertSame('https://github.com/testuser', $user->htmlUrl);
+        $this->assertSame('User', $user->type);
+    }
+
+    public function testConstructorWithDefaultType(): void
+    {
+        $user = new GithubUser(
+            login: 'bot',
+            id: 67890,
+            avatarUrl: 'https://avatar.example.com/bot.png',
+            htmlUrl: 'https://github.com/bot'
+        );
+
+        $this->assertSame('User', $user->type);
+    }
+
+    public function testToStringReturnsLogin(): void
+    {
+        $user = new GithubUser(
+            login: 'testuser',
+            id: 12345,
+            avatarUrl: 'https://avatar.example.com/testuser.png',
+            htmlUrl: 'https://github.com/testuser'
+        );
+
+        $this->assertSame('testuser', (string) $user);
+    }
+
+    public function testFromApiResponseWithCompleteData(): void
+    {
+        $data = (object) [
+            'login' => 'apiuser',
+            'id' => 99999,
+            'avatar_url' => 'https://avatar.example.com/apiuser.png',
+            'html_url' => 'https://github.com/apiuser',
+            'type' => 'Bot'
+        ];
+
+        $user = GithubUser::fromApiResponse($data);
+
+        $this->assertSame('apiuser', $user->login);
+        $this->assertSame(99999, $user->id);
+        $this->assertSame('https://avatar.example.com/apiuser.png', $user->avatarUrl);
+        $this->assertSame('https://github.com/apiuser', $user->htmlUrl);
+        $this->assertSame('Bot', $user->type);
+    }
+
+    public function testFromApiResponseWithMinimalData(): void
+    {
+        $data = (object) [];
+
+        $user = GithubUser::fromApiResponse($data);
+
+        $this->assertSame('', $user->login);
+        $this->assertSame(0, $user->id);
+        $this->assertSame('', $user->avatarUrl);
+        $this->assertSame('', $user->htmlUrl);
+        $this->assertSame('User', $user->type);
+    }
+
+    public function testFromApiResponseWithPartialData(): void
+    {
+        $data = (object) [
+            'login' => 'partial',
+            'id' => 54321
+        ];
+
+        $user = GithubUser::fromApiResponse($data);
+
+        $this->assertSame('partial', $user->login);
+        $this->assertSame(54321, $user->id);
+        $this->assertSame('', $user->avatarUrl);
+        $this->assertSame('', $user->htmlUrl);
+        $this->assertSame('User', $user->type);
+    }
+}
diff --git a/test/unit/MergeTest.php b/test/unit/MergeTest.php
new file mode 100644
index 0000000..dce81f5
--- /dev/null
+++ b/test/unit/MergeTest.php
@@ -0,0 +1,169 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\MergePullRequestParams;
+use Horde\GithubApiClient\MergeResult;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(MergePullRequestParams::class)]
+#[CoversClass(MergeResult::class)]
+class MergeTest extends TestCase
+{
+    public function testMergePullRequestParamsConstructorDefaults(): void
+    {
+        $params = new MergePullRequestParams();
+
+        $this->assertSame('', $params->commitTitle);
+        $this->assertSame('', $params->commitMessage);
+        $this->assertSame('merge', $params->mergeMethod);
+        $this->assertSame('', $params->sha);
+    }
+
+    public function testMergePullRequestParamsConstructorWithAllParameters(): void
+    {
+        $params = new MergePullRequestParams(
+            commitTitle: 'Merge pull request #123',
+            commitMessage: 'This PR adds feature X',
+            mergeMethod: 'squash',
+            sha: 'abc123def456'
+        );
+
+        $this->assertSame('Merge pull request #123', $params->commitTitle);
+        $this->assertSame('This PR adds feature X', $params->commitMessage);
+        $this->assertSame('squash', $params->mergeMethod);
+        $this->assertSame('abc123def456', $params->sha);
+    }
+
+    public function testMergePullRequestParamsToArrayWithDefaults(): void
+    {
+        $params = new MergePullRequestParams();
+        $array = $params->toArray();
+
+        $this->assertSame([], $array);
+    }
+
+    public function testMergePullRequestParamsToArrayWithAllFields(): void
+    {
+        $params = new MergePullRequestParams(
+            commitTitle: 'Test title',
+            commitMessage: 'Test message',
+            mergeMethod: 'squash',
+            sha: 'abc123'
+        );
+        $array = $params->toArray();
+
+        $this->assertSame([
+            'commit_title' => 'Test title',
+            'commit_message' => 'Test message',
+            'merge_method' => 'squash',
+            'sha' => 'abc123'
+        ], $array);
+    }
+
+    public function testMergePullRequestParamsToArrayExcludesDefaultMergeMethod(): void
+    {
+        $params = new MergePullRequestParams(
+            commitTitle: 'Test',
+            mergeMethod: 'merge'
+        );
+        $array = $params->toArray();
+
+        $this->assertArrayHasKey('commit_title', $array);
+        $this->assertArrayNotHasKey('merge_method', $array);
+    }
+
+    public function testMergePullRequestParamsMergeMethods(): void
+    {
+        // merge
+        $mergeParams = new MergePullRequestParams(mergeMethod: 'merge');
+        $this->assertSame('merge', $mergeParams->mergeMethod);
+
+        // squash
+        $squashParams = new MergePullRequestParams(mergeMethod: 'squash');
+        $this->assertSame('squash', $squashParams->mergeMethod);
+
+        // rebase
+        $rebaseParams = new MergePullRequestParams(mergeMethod: 'rebase');
+        $this->assertSame('rebase', $rebaseParams->mergeMethod);
+    }
+
+    public function testMergeResultConstructor(): void
+    {
+        $result = new MergeResult(
+            sha: 'def789ghi012',
+            merged: true,
+            message: 'Pull Request successfully merged'
+        );
+
+        $this->assertSame('def789ghi012', $result->sha);
+        $this->assertTrue($result->merged);
+        $this->assertSame('Pull Request successfully merged', $result->message);
+    }
+
+    public function testMergeResultToStringWhenMerged(): void
+    {
+        $result = new MergeResult(
+            sha: 'abc123',
+            merged: true,
+            message: 'Merged successfully'
+        );
+
+        $this->assertSame('Merged: Merged successfully (abc123)', (string) $result);
+    }
+
+    public function testMergeResultToStringWhenNotMerged(): void
+    {
+        $result = new MergeResult(
+            sha: '',
+            merged: false,
+            message: 'Pull request is not mergeable'
+        );
+
+        $this->assertSame('Not merged: Pull request is not mergeable', (string) $result);
+    }
+
+    public function testMergeResultFromApiResponseWhenMerged(): void
+    {
+        $data = (object) [
+            'sha' => 'ghi789jkl012',
+            'merged' => true,
+            'message' => 'Pull Request successfully merged'
+        ];
+
+        $result = MergeResult::fromApiResponse($data);
+
+        $this->assertSame('ghi789jkl012', $result->sha);
+        $this->assertTrue($result->merged);
+        $this->assertSame('Pull Request successfully merged', $result->message);
+    }
+
+    public function testMergeResultFromApiResponseWhenNotMerged(): void
+    {
+        $data = (object) [
+            'sha' => '',
+            'merged' => false,
+            'message' => 'Merge conflict'
+        ];
+
+        $result = MergeResult::fromApiResponse($data);
+
+        $this->assertSame('', $result->sha);
+        $this->assertFalse($result->merged);
+        $this->assertSame('Merge conflict', $result->message);
+    }
+
+    public function testMergeResultFromApiResponseWithMinimalData(): void
+    {
+        $data = (object) [];
+
+        $result = MergeResult::fromApiResponse($data);
+
+        $this->assertSame('', $result->sha);
+        $this->assertFalse($result->merged);
+        $this->assertSame('', $result->message);
+    }
+}
diff --git a/test/unit/PullRequestUpdateTest.php b/test/unit/PullRequestUpdateTest.php
new file mode 100644
index 0000000..c9ce97c
--- /dev/null
+++ b/test/unit/PullRequestUpdateTest.php
@@ -0,0 +1,135 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\GithubApiClient\Test\Unit;
+
+use Horde\GithubApiClient\PullRequestUpdate;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(PullRequestUpdate::class)]
+class PullRequestUpdateTest extends TestCase
+{
+    public function testConstructorWithAllFields(): void
+    {
+        $update = new PullRequestUpdate(
+            title: 'feat: new feature',
+            body: 'This PR adds a new feature',
+            base: 'main',
+            state: 'open'
+        );
+
+        $this->assertSame('feat: new feature', $update->title);
+        $this->assertSame('This PR adds a new feature', $update->body);
+        $this->assertSame('main', $update->base);
+        $this->assertSame('open', $update->state);
+    }
+
+    public function testConstructorWithOnlyTitle(): void
+    {
+        $update = new PullRequestUpdate(title: 'Updated title');
+
+        $this->assertSame('Updated title', $update->title);
+        $this->assertNull($update->body);
+        $this->assertNull($update->base);
+        $this->assertNull($update->state);
+    }
+
+    public function testConstructorWithNoFields(): void
+    {
+        $update = new PullRequestUpdate();
+
+        $this->assertNull($update->title);
+        $this->assertNull($update->body);
+        $this->assertNull($update->base);
+        $this->assertNull($update->state);
+    }
+
+    public function testToArrayIncludesOnlySetFields(): void
+    {
+        $update = new PullRequestUpdate(
+            title: 'New title',
+            state: 'closed'
+        );
+
+        $array = $update->toArray();
+
+        $this->assertArrayHasKey('title', $array);
+        $this->assertArrayHasKey('state', $array);
+        $this->assertArrayNotHasKey('body', $array);
+        $this->assertArrayNotHasKey('base', $array);
+        $this->assertSame('New title', $array['title']);
+        $this->assertSame('closed', $array['state']);
+    }
+
+    public function testToArrayWithAllFields(): void
+    {
+        $update = new PullRequestUpdate(
+            title: 'Title',
+            body: 'Body',
+            base: 'develop',
+            state: 'open'
+        );
+
+        $array = $update->toArray();
+
+        $this->assertCount(4, $array);
+        $this->assertSame('Title', $array['title']);
+        $this->assertSame('Body', $array['body']);
+        $this->assertSame('develop', $array['base']);
+        $this->assertSame('open', $array['state']);
+    }
+
+    public function testToArrayWithNoFields(): void
+    {
+        $update = new PullRequestUpdate();
+
+        $array = $update->toArray();
+
+        $this->assertEmpty($array);
+        $this->assertIsArray($array);
+    }
+
+    public function testIsEmptyReturnsTrueWhenNoFieldsSet(): void
+    {
+        $update = new PullRequestUpdate();
+
+        $this->assertTrue($update->isEmpty());
+    }
+
+    public function testIsEmptyReturnsFalseWhenTitleSet(): void
+    {
+        $update = new PullRequestUpdate(title: 'Test');
+
+        $this->assertFalse($update->isEmpty());
+    }
+
+    public function testIsEmptyReturnsFalseWhenBodySet(): void
+    {
+        $update = new PullRequestUpdate(body: 'Test body');
+
+        $this->assertFalse($update->isEmpty());
+    }
+
+    public function testIsEmptyReturnsFalseWhenBaseSet(): void
+    {
+        $update = new PullRequestUpdate(base: 'main');
+
+        $this->assertFalse($update->isEmpty());
+    }
+
+    public function testIsEmptyReturnsFalseWhenStateSet(): void
+    {
+        $update = new PullRequestUpdate(state: 'closed');
+
+        $this->assertFalse($update->isEmpty());
+    }
+
+    public function testIsEmptyReturnsFalseWhenMultipleFieldsSet(): void
+    {
+        $update = new PullRequestUpdate(title: 'Title', body: 'Body');
+
+        $this->assertFalse($update->isEmpty());
+    }
+}