diff --git a/README.md b/README.md
index f879030..642a059 100644
--- a/README.md
+++ b/README.md
@@ -144,6 +144,12 @@ The template points PHP tooling at `.ddev/drupal-code-quality/tooling/bin` and J
     by `.cspell.json` `ignorePaths`. Narrow the scan by passing explicit paths.
   - `.cspell-project-words.txt` is created by the installer (empty) and updated
     by `ddev cspell-suggest` when you accept suggested words.
+- PHPCS / PHPCBF default scope:
+  - When a project `.phpcs.xml` is installed by the add-on, `ddev phpcs` and
+    `ddev phpcbf` with no path default to scanning the configured docroot.
+  - The generated ruleset excludes `__DOCROOT__/core/**`, `**/contrib/**`,
+    `**/node_modules/**`, and `__DOCROOT__/sites/*/files/**`.
+  - You can still pass explicit paths to narrow runs.
 - PHPStan baseline:
   - Generate a baseline with `ddev phpstan --generate-baseline`.
   - This writes `phpstan-baseline.neon` at the project root; the wrapper will
diff --git a/drupal-code-quality/config-amendments/.phpcs.dcq.xml b/drupal-code-quality/config-amendments/.phpcs.dcq.xml
index da933ce..6338f45 100644
--- a/drupal-code-quality/config-amendments/.phpcs.dcq.xml
+++ b/drupal-code-quality/config-amendments/.phpcs.dcq.xml
@@ -4,5 +4,10 @@
 
   <rule ref="DrupalPractice"/>
 
+  <!-- Default to scanning the Drupal docroot when no path is provided. -->
+  <file>__DOCROOT__</file>
+
+  <exclude-pattern>__DOCROOT__/core/**</exclude-pattern>
+  <exclude-pattern>**/contrib/**</exclude-pattern>
   <exclude-pattern>**/node_modules/**</exclude-pattern>
   <exclude-pattern>__DOCROOT__/sites/*/files/**</exclude-pattern>
diff --git a/tests/test.bats b/tests/test.bats
index 052b9e9..3ede975 100644
--- a/tests/test.bats
+++ b/tests/test.bats
@@ -934,8 +934,16 @@ PY
   assert_success
   run grep -n "web/core" ".cspell.json"
   assert_failure
+  run grep -n '<rule ref="DrupalPractice"/>' ".phpcs.xml"
+  assert_success
+  run grep -n "<file>docroot</file>" ".phpcs.xml"
+  assert_success
+  run grep -n "docroot/core/\\*\\*" ".phpcs.xml"
+  assert_success
   run grep -n "docroot/sites" ".phpcs.xml"
   assert_success
+  run grep -n "__DOCROOT__" ".phpcs.xml"
+  assert_failure
 
   # Verify PHPStan config uses custom docroot
   run grep -q "docroot/modules/custom" phpstan.neon