Add support for updating extension sources and names (#21715)

docs/extensions/reference.md

@@ -123,6 +123,7 @@ The manifest file defines the extension's behavior and configuration.
   },
   "contextFileName": "GEMINI.md",
   "excludeTools": ["run_shell_command"],
+  "migratedTo": "https://github.com/new-owner/new-extension-repo",
   "plan": {
     "directory": ".gemini/plans"
   }
@@ -138,6 +139,9 @@ The manifest file defines the extension's behavior and configuration.
 - `version`: The version of the extension.
 - `description`: A short description of the extension. This will be displayed on
   [geminicli.com/extensions](https://geminicli.com/extensions).
+- `migratedTo`: The URL of the new repository source for the extension. If this
+  is set, the CLI will automatically check this new source for updates and
+  migrate the extension's installation to the new source if an update is found.
 - `mcpServers`: A map of MCP servers to settings. The key is the name of the
   server, and the value is the server configuration. These servers will be
   loaded on startup just like MCP servers defined in a

docs/extensions/releasing.md

@@ -152,3 +152,29 @@ jobs:
             release/linux.arm64.my-tool.tar.gz
             release/win32.arm64.my-tool.zip
 ```
+
+## Migrating an Extension Repository
+
+If you need to move your extension to a new repository (e.g., from a personal
+account to an organization) or rename it, you can use the `migratedTo` property
+in your `gemini-extension.json` file to seamlessly transition your users.
+
+1. **Create the new repository**: Setup your extension in its new location.
+2. **Update the old repository**: In your original repository, update the
+   `gemini-extension.json` file to include the `migratedTo` property, pointing
+   to the new repository URL, and bump the version number. You can optionally
+   change the `name` of your extension at this time in the new repository.
+   ```json
+   {
+     "name": "my-extension",
+     "version": "1.1.0",
+     "migratedTo": "https://github.com/new-owner/new-extension-repo"
+   }
+   ```
+3. **Release the update**: Publish this new version in your old repository.
+
+When users check for updates, the Gemini CLI will detect the `migratedTo` field,
+verify that the new repository contains a valid extension update, and
+automatically update their local installation to track the new source and name
+moving forward. All extension settings will automatically migrate to the new
+installation.