[CLI] Settings slash command (#61633)

Co-authored-by: vgrltwin <vgrl+twin@github.com>
Co-authored-by: Vanessa <vgrl@github.com>
Co-authored-by: Ben Ahmady <32935794+subatoi@users.noreply.github.com>

Author: 4 people

content/copilot/how-tos/copilot-cli/use-copilot-cli/overview.md

@@ -283,6 +283,18 @@ You can run {% data variables.copilot.copilot_cli_short %} sessions inside a san
 
 Press <kbd>Ctrl</kbd>+<kbd>T</kbd> to show or hide the model's reasoning process while it generates a response. This setting persists across sessions, allowing you to observe how {% data variables.product.prodname_copilot_short %} works through complex problems.
 
+### Configure settings
+
+You can view and change {% data variables.copilot.copilot_cli_short %} settings using the `/settings` slash command.
+
+* Run `/settings` to open an interactive settings dialog, where you can search for a setting by name and edit it.
+* Run `/settings KEY VALUE` to set a setting inline, where KEY is the name of the setting and VALUE is the value you want to set. This also works in scripts and in programmatic sessions started with `-p`.
+* Run `/settings reset KEY` to restore a setting to its default value.
+
+Some settings, such as the color mode, take effect immediately when you save them.
+
+For the full list of available settings, see [AUTOTITLE](/copilot/reference/copilot-cli-reference/cli-config-dir-reference#configuration-file-settings).
+
 ## Find out more
 
 For a complete list of the command line options and slash commands that you can use with {% data variables.copilot.copilot_cli_short %}, do one of the following:

content/copilot/reference/copilot-cli-reference/cli-command-reference.md

@@ -244,6 +244,7 @@ Holding <kbd>↑</kbd> or <kbd>↓</kbd> accelerates scrolling after the first 1
 | `/sandbox [enable\|disable]`                        | Configure shell command sandboxing. |
 | `/search [QUERY]`, `/find [QUERY]`                  | Search the conversation timeline. {% data reusables.copilot.experimental %} |
 | `/session [info\|checkpoints [n]\|files\|plan\|rename [NAME]\|cleanup\|prune\|delete [ID]\|delete-all]`, `/sessions [info\|checkpoints [n]\|files\|plan\|rename [NAME]\|cleanup\|prune\|delete [ID]\|delete-all]`  | Show session information and manage sessions. The `info` subcommand shows session details including the session link (when available). Subcommands: `info`, `checkpoints`, `files`, `plan`, `rename`, `cleanup`, `prune`, `delete`, `delete-all`. |
+| `/settings [show\|[KEY VALUE]\|reset KEY]`  | Open the settings dialog, set a setting inline with a KEY and VALUE, or reset a setting to its default. See [AUTOTITLE](/copilot/reference/copilot-cli-reference/cli-config-dir-reference#configuration-file-settings). |
 | `/share [file\|html\|gist] [session\|research] [PATH]`, `/export [file\|html\|gist] [session\|research] [PATH]` | Share the session to a Markdown file, interactive HTML file, or {% data variables.product.github %} gist. |
 | `/skills [list\|info\|add\|remove\|reload] [ARGS...]`   | Manage skills for enhanced capabilities. See [AUTOTITLE](/copilot/how-tos/copilot-cli/customize-copilot/create-skills). |
 | `/statusline`, `/footer`                            | Configure which items appear in the status line. |

content/copilot/reference/copilot-cli-reference/cli-config-dir-reference.md

@@ -50,7 +50,7 @@ The following files are designed to be edited by you directly, or managed throug
 
 ### `settings.json`
 
-This is the primary configuration file for {% data variables.copilot.copilot_cli_short %}. You can edit it directly in a text editor, or use interactive commands like `/model` and `/theme` to change specific values from within a session. The file supports JSON with comments (JSONC).
+This is the primary configuration file for {% data variables.copilot.copilot_cli_short %}. Within a session, you can use the interactive `/settings` command to change specific values, or run `/settings KEY VALUE` to set a single value, or edit the file directly in a text editor. The file supports JSON with comments (JSONC).
 
 > [!NOTE]
 > User-editable settings were originally stored in `config.json`. They have been moved to `settings.json`. Any user settings present in `config.json` on startup are automatically migrated to `settings.json`.
@@ -204,7 +204,7 @@ Settings cascade from user to repository to local, with more specific scopes ove
 
 ### User settings (`~/.copilot/settings.json`)
 
-These settings apply across all your sessions and repositories. You can edit this file directly, or use slash commands to update individual values.
+These settings apply across all your sessions and repositories. You can use the `/settings` slash command to run an interactive dialog, or use specific slash commands to update individual values, or edit this file directly.
 
 | Key | Type | Default | Description |
 |-----|------|---------|-------------|