diff --git a/packages/components/AGENTS.md b/packages/components/AGENTS.md
index ff2cad80eca2d4..41431329c99fbb 100644
--- a/packages/components/AGENTS.md
+++ b/packages/components/AGENTS.md
@@ -15,3 +15,13 @@ For adding validation, consider using the [Validated Form Components](./src/vali
 ## Storybook
 
 Don't forget to check a components's Storybook documentation for additional usage guidance. The Storybook links ([public base URL](https://wordpress.github.io/gutenberg/)) are also useful to present to a human when they are asking for help with a component.
+
+## Changelogs
+
+Add an entry to `CHANGELOG.md` for any change in this package.
+
+-   Add the entry under `## Unreleased` at the top of the file. If that heading doesn't exist (i.e. the previous release header is at the top), add it.
+-   One entry per PR, not per commit. If the branch already has a bullet under `## Unreleased` for this PR, edit it to cover any follow-up commits rather than adding a second bullet.
+-   Pick the right sub-heading per the canonical guidance in [`packages/README.md`](../README.md#maintaining-changelogs) (`Breaking Changes`, `Deprecations`, `New Features`, `Enhancements`, `Bug Fixes`, `Internal`, etc.).
+-   When the change is scoped to one or a small number of components, prefix the bullet with the component name(s) in backticks — e.g. `` `Button`: Fix … ``. Omit the prefix for broad cross-cutting changes (build config, shared utilities, repo-wide refactors).
+-   Once the PR exists, append `([#NNNNN](https://github.com/WordPress/gutenberg/pull/NNNNN))` to the end of the bullet. If the PR number isn't known yet, omit the parenthetical.
diff --git a/packages/theme/AGENTS.md b/packages/theme/AGENTS.md
new file mode 100644
index 00000000000000..c29e5c3883ec91
--- /dev/null
+++ b/packages/theme/AGENTS.md
@@ -0,0 +1,8 @@
+## Changelogs
+
+Add an entry to `CHANGELOG.md` for any change in this package.
+
+-   Add the entry under `## Unreleased` at the top of the file. If that heading doesn't exist (i.e. the previous release header is at the top), add it.
+-   One entry per PR, not per commit. If the branch already has a bullet under `## Unreleased` for this PR, edit it to cover any follow-up commits rather than adding a second bullet.
+-   Pick the right sub-heading per the canonical guidance in [`packages/README.md`](../README.md#maintaining-changelogs) (`Breaking Changes`, `Deprecations`, `New Features`, `Enhancements`, `Bug Fixes`, `Internal`, etc.).
+-   Once the PR exists, append `([#NNNNN](https://github.com/WordPress/gutenberg/pull/NNNNN))` to the end of the bullet. If the PR number isn't known yet, omit the parenthetical.
diff --git a/packages/theme/CLAUDE.md b/packages/theme/CLAUDE.md
new file mode 100644
index 00000000000000..43c994c2d3617f
--- /dev/null
+++ b/packages/theme/CLAUDE.md
@@ -0,0 +1 @@
+@AGENTS.md
diff --git a/packages/ui/AGENTS.md b/packages/ui/AGENTS.md
new file mode 100644
index 00000000000000..72ac1394ecc3e0
--- /dev/null
+++ b/packages/ui/AGENTS.md
@@ -0,0 +1,9 @@
+## Changelogs
+
+Add an entry to `CHANGELOG.md` for any change in this package.
+
+-   Add the entry under `## Unreleased` at the top of the file. If that heading doesn't exist (i.e. the previous release header is at the top), add it.
+-   One entry per PR, not per commit. If the branch already has a bullet under `## Unreleased` for this PR, edit it to cover any follow-up commits rather than adding a second bullet.
+-   Pick the right sub-heading per the canonical guidance in [`packages/README.md`](../README.md#maintaining-changelogs) (`Breaking Changes`, `Deprecations`, `New Features`, `Enhancements`, `Bug Fixes`, `Internal`, etc.).
+-   When the change is scoped to one or a small number of components, prefix the bullet with the component name(s) in backticks — e.g. `` `Select`: Fix … ``. Omit the prefix for broad cross-cutting changes (build config, shared utilities, repo-wide refactors).
+-   Once the PR exists, append `([#NNNNN](https://github.com/WordPress/gutenberg/pull/NNNNN))` to the end of the bullet. If the PR number isn't known yet, omit the parenthetical.
diff --git a/packages/ui/CLAUDE.md b/packages/ui/CLAUDE.md
new file mode 100644
index 00000000000000..43c994c2d3617f
--- /dev/null
+++ b/packages/ui/CLAUDE.md
@@ -0,0 +1 @@
+@AGENTS.md