feat(plan): enable Plan Mode by default (#21713)

docs/cli/plan-mode.md

@@ -1,4 +1,4 @@
-# Plan Mode (experimental)
+# Plan Mode
 
 Plan Mode is a read-only environment for architecting robust solutions before
 implementation. With Plan Mode, you can:
@@ -8,27 +8,8 @@ implementation. With Plan Mode, you can:
 - **Design:** Understand problems, evaluate trade-offs, and choose a solution.
 - **Plan:** Align on an execution strategy before any code is modified.
 
-> **Note:** This is a preview feature currently under active development. Your
-> feedback is invaluable as we refine this feature. If you have ideas,
-> suggestions, or encounter issues:
->
-> - [Open an issue] on GitHub.
-> - Use the **/bug** command within Gemini CLI to file an issue.
-
-## How to enable Plan Mode
-
-Enable Plan Mode in **Settings** or by editing your configuration file.
-
-- **Settings:** Use the `/settings` command and set **Plan** to `true`.
-- **Configuration:** Add the following to your `settings.json`:
-
-  ```json
-  {
-    "experimental": {
-      "plan": true
-    }
-  }
-  ```
+Plan Mode is enabled by default. You can manage this setting using the
+`/settings` command.
 
 ## How to enter Plan Mode
 

docs/cli/settings.md

@@ -144,7 +144,7 @@ they appear in the UI.
 | Enable Tool Output Masking | `experimental.toolOutputMasking.enabled` | Enables tool output masking to save tokens.                                                                                                               | `true`  |
 | Use OSC 52 Paste           | `experimental.useOSC52Paste`             | Use OSC 52 for pasting. This may be more robust than the default system when using remote terminal sessions (if your terminal is configured to allow it). | `false` |
 | Use OSC 52 Copy            | `experimental.useOSC52Copy`              | Use OSC 52 for copying. This may be more robust than the default system when using remote terminal sessions (if your terminal is configured to allow it). | `false` |
-| Plan                       | `experimental.plan`                      | Enable planning features (Plan Mode and tools).                                                                                                           | `false` |
+| Plan                       | `experimental.plan`                      | Enable Plan Mode.                                                                                                                                         | `true`  |
 | Model Steering             | `experimental.modelSteering`             | Enable model steering (user hints) to guide the model during tool execution.                                                                              | `false` |
 | Direct Web Fetch           | `experimental.directWebFetch`            | Enable web fetch behavior that bypasses LLM summarization.                                                                                                | `false` |
 

docs/reference/commands.md

@@ -279,8 +279,8 @@ Slash commands provide meta-level control over the CLI itself.
 
 - **Description:** Switch to Plan Mode (read-only) and view the current plan if
   one has been generated.
-  - **Note:** This feature requires the `experimental.plan` setting to be
-    enabled in your configuration.
+  - **Note:** This feature is enabled by default. It can be disabled via the
+    `experimental.plan` setting in your configuration.
 - **Sub-commands:**
   - **`copy`**:
     - **Description:** Copy the currently approved plan to your clipboard.

docs/reference/configuration.md

@@ -1021,8 +1021,8 @@ their corresponding top-level category object in your `settings.json` file.
   - **Default:** `false`
 
 - **`experimental.plan`** (boolean):
-  - **Description:** Enable planning features (Plan Mode and tools).
-  - **Default:** `false`
+  - **Description:** Enable Plan Mode.
+  - **Default:** `true`
   - **Requires restart:** Yes
 
 - **`experimental.taskTracker`** (boolean):