docs: access keys and guards references in typescript

Signed-off-by: David Dal Busco <david.dalbusco@outlook.com>

Author: peterpeterparker

docs/reference/functions/typescript/sdk.mdx

@@ -541,3 +541,115 @@ function getContentChunksStore(
 
 - `ZodError` if the input schema is invalid.
 - `Error` if the operation fails.
+
+---
+
+## Access Keys
+
+The following functions allow you to inspect and assert the access keys of your Satellite.
+
+---
+
+### getAccessKeys
+
+Retrieves all access keys of the Satellite.
+
+```typescript
+function getAccessKeys(): AccessKeys;
+```
+
+📦 Import from `@junobuild/functions/sdk`
+
+#### Returns:
+
+- `AccessKeys`: The list of all access keys.
+
+#### Throws:
+
+- `ZodError` if the returned value does not match the expected schema.
+
+---
+
+### getAdminAccessKeys
+
+Retrieves only the admin access keys of the Satellite.
+
+```typescript
+function getAdminAccessKeys(): AccessKeys;
+```
+
+📦 Import from `@junobuild/functions/sdk`
+
+#### Returns:
+
+- `AccessKeys`: The list of admin access keys.
+
+#### Throws:
+
+- `ZodError` if the returned value does not match the expected schema.
+
+---
+
+## Guards
+
+The following guard functions can be used to validate the caller in your custom serverless functions.
+
+---
+
+### callerIsAdmin
+
+Guards that the caller is an admin access key of this satellite. Admin access keys have full management privileges and never expire.
+
+```typescript
+function callerIsAdmin(): void;
+```
+
+📦 Import from `@junobuild/functions/sdk`
+
+#### Returns:
+
+- `void`
+
+#### Throws:
+
+- `ZodError` if the caller is not an admin access key.
+
+---
+
+### callerHasWritePermission
+
+Guards that the caller has write permission. Admin and editor access keys pass; submitter access keys do not.
+
+```typescript
+function callerHasWritePermission(): void;
+```
+
+📦 Import from `@junobuild/functions/sdk`
+
+#### Returns:
+
+- `void`
+
+#### Throws:
+
+- `ZodError` if the caller does not have write permission.
+
+---
+
+### callerIsAccessKey
+
+Guards that the caller is any recognized access key of this satellite. Accepts admin, editor, and submitter access keys alike.
+
+```typescript
+function callerIsAccessKey(): void;
+```
+
+📦 Import from `@junobuild/functions/sdk`
+
+#### Returns:
+
+- `void`
+
+#### Throws:
+
+- `ZodError` if the caller is not a recognized access key.