feat(cli): refactor model command to support set and manage subcommands

[sehoon38]

Summary

Refactored the /model slash command in the CLI to support subcommands (set and manage). This provides a more consistent interface for both opening the model management dialog and quickly switching models via the terminal.

Details

• Added subCommands support to the modelCommand definition.
• Implemented /model set <model-name> [--persist] to update the current model.
• Implemented /model manage to open the existing model configuration dialog.
• Simplified modelCommand.action to delegate to manageModelCommand, consistent with the stats command routing.
• Updated tests to cover the new functionality.

Related Issues

Related to #19166 (improving CLI command structure).

How to Validate

1. Run the CLI: npm run start
2. Test default behavior: Type /model and press Enter. It should open the model management dialog.
3. Test manage subcommand: Type /model manage and press Enter. It should also open the dialog.
4. Test set subcommand: Type /model set gemini-1.5-flash and press Enter. It should update the model.
5. Test set with persistence: Type /model set gemini-1.5-pro --persist. It should update the model and persist it to config.
6. Verify error handling: Type /model set without arguments. It should show a usage error.

Pre-Merge Checklist

• Updated relevant documentation and README (if needed)
• Added/updated tests (if needed)
• Noted breaking changes (if any)
• Validated on required platforms/methods:
  • MacOS
    • npm run

[gemini-cli]

Hi @sehoon38, thank you so much for your contribution to Gemini CLI! We really appreciate the time and effort you've put into this.

We're making some updates to our contribution process to improve how we track and review changes. Please take a moment to review our recent discussion post: Improving Our Contribution Process & Introducing New Guidelines.

Key Update: Starting January 26, 2026, the Gemini CLI project will require all pull requests to be associated with an existing issue. Any pull requests not linked to an issue by that date will be automatically closed.

Thank you for your understanding and for being a part of our community!

[gemini-code-assist]

Summary of Changes

Hello @sehoon38, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the /model command in the CLI by introducing a subcommand structure. This refactoring provides a more intuitive and powerful interface for users to either quickly switch between models using /model set or access the full model management dialog via /model manage or the default /model command. The changes streamline model interaction within the terminal, improving user experience and command consistency.

Highlights

• Subcommand Support: The /model CLI command now supports subcommands, specifically set and manage, providing a more structured interface.
• Model Setting Functionality: A new /model set <model-name> [--persist] subcommand allows users to quickly change the active model, with an option to persist the change across sessions.
• Dedicated Model Management Dialog: The /model manage subcommand explicitly opens the model configuration dialog, which remains the default behavior for /model without arguments.
• Refactored Action Routing: The main modelCommand action has been refactored to correctly delegate to its subcommands based on user input, improving command parsing.
• Enhanced Test Coverage: Comprehensive tests were added and updated to ensure the correct functionality and routing of the new subcommands, including model setting, persistence, and error handling.

Changelog

• packages/cli/src/ui/commands/modelCommand.test.ts
  • Imported MessageType for testing UI messages.
  • Updated existing test descriptions for clarity, distinguishing between default /model behavior and subcommand behavior.
  • Added new test suites for the manage subcommand, verifying it opens the model dialog and calls refreshUserQuota.
  • Added new test suites for the set subcommand, covering model setting, persistence, and error handling for missing arguments.
  • Adjusted the expected description for modelCommand to reflect its new role as a manager of subcommands.
• packages/cli/src/ui/commands/modelCommand.ts
  • Imported necessary logging utilities (ModelSlashCommandEvent, logModelSlashCommand) and MessageType.
  • Introduced setModelCommand as a new SlashCommand to handle setting the current model, including logic for parsing model name and --persist flag, and displaying UI messages.
  • Introduced manageModelCommand as a new SlashCommand to specifically open the model configuration dialog.
  • Refactored the main modelCommand to act as a container for subCommands (manageModelCommand and setModelCommand).
  • Modified the modelCommand's action to intelligently route incoming arguments to the appropriate subcommand or default to manageModelCommand if no specific subcommand is provided.
  • Updated the modelCommand's description to reflect its new role as a model configuration manager.

Activity

• The author has confirmed that relevant documentation and READMEs have been updated.
• The author has confirmed that tests have been added/updated.
• The author has validated the changes on MacOS using npm run.

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[gemini-code-assist]

Code Review

This pull request effectively refactors the /model command to use a subcommand structure, which improves the CLI's consistency and usability. The introduction of /model set for quick model switching and /model manage for the UI dialog is a good enhancement.

My main feedback is on the implementation of the new parent modelCommand's action. The current logic for handling subcommands has a flaw where it defaults to the manage action for any invalid subcommand, which is not ideal for user experience. It's also not easily maintainable. I've left a specific comment with a suggested refactoring to address this by showing a proper error message and making the subcommand lookup more robust.

Overall, this is a solid refactoring. Addressing the feedback will make it even better.

[github-actions]

Size Change: +1.22 kB (0%)

Total Size: 24.4 MB

Filename	Size	Change
./bundle/gemini.js	24.4 MB	+1.22 kB (0%)

ℹ️ View Unchanged

Filename	Size
./bundle/sandbox-macos-permissive-open.sb	890 B
./bundle/sandbox-macos-permissive-proxied.sb	1.31 kB
./bundle/sandbox-macos-restrictive-open.sb	3.36 kB
./bundle/sandbox-macos-restrictive-proxied.sb	3.56 kB
./bundle/sandbox-macos-strict-open.sb	4.82 kB
./bundle/sandbox-macos-strict-proxied.sb	5.02 kB

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