refactor(core): replace manual syncPlanModeTools with declarative policy rules

[jerop]

Unified plan-related tool visibility management by leveraging the existing Policy Engine instead of imperative registration/unregistration.

Key changes:

• Removed syncPlanModeTools from Config class and its calls during initialization and mode transitions.
• Added declarative DENY rules to plan.toml, write.toml, and yolo.toml to control enter_plan_mode and exit_plan_mode visibility based on the current ApprovalMode.

Closes #20595

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Plan mode has ExitPlanMode tool

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Default mode has EnterPlanMode tool

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Auto-Edit mode has EnterPlanMode tool

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YOLO mode does not have EnterPlanMode or EnterPlanMode tools

[gemini-code-assist]

Summary of Changes

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This pull request refactors the management of plan-related tool visibility by transitioning from an imperative, code-driven synchronization mechanism to a declarative, policy-based approach. This change centralizes tool visibility logic within the Policy Engine, making it more consistent and easier to manage across different operational modes. The primary impact is a cleaner, more robust system for controlling which tools are available to the model based on the current approval mode, enhancing maintainability and reducing potential for inconsistencies.

Highlights

• Removed imperative tool synchronization: The manual syncPlanModeTools method from the Config class and its calls during initialization and mode transitions have been removed.
• Introduced declarative policy rules: New DENY rules were added to plan.toml, write.toml, and yolo.toml to control the visibility of enter_plan_mode and exit_plan_mode based on the current ApprovalMode.
• Updated tool registration logic: The Config.createToolRegistry now unconditionally registers plan tools if the feature is enabled, relying on policy rules for visibility control.
• Refactored approval mode updates: The updateApprovalMode method now refreshes the model's toolset via geminiClient.setTools() when transitioning between modes, ensuring policies are re-evaluated.
• Revised test suite: Existing tests were updated to reflect the new policy-based filtering, and obsolete syncPlanModeTools tests were removed.

Changelog

• packages/core/src/config/config.test.ts
  • Removed imports for ExitPlanModeTool and EnterPlanModeTool.
  • Added a new test case to verify EnterPlanModeTool and ExitPlanModeTool are registered when the plan feature is enabled.
  • Removed the entire describe('syncPlanModeTools', ...) test block, as the method was removed.
• packages/core/src/config/config.ts
  • Removed imports for ENTER_PLAN_MODE_TOOL_NAME and EXIT_PLAN_MODE_TOOL_NAME.
  • Removed the call to this.syncPlanModeTools() during initialize().
  • Removed the syncPlanModeTools() method entirely.
  • Modified updateApprovalMode() to directly call this.geminiClient.setTools() when a plan or YOLO mode transition occurs, replacing the call to syncPlanModeTools().
• packages/core/src/policy/policies/plan.toml
  • Added a new rule to deny enter_plan_mode when the system is already in 'plan' mode, with a specific deny message.
• packages/core/src/policy/policies/write.toml
  • Added a new rule to deny exit_plan_mode when the system is in 'default' or 'autoEdit' modes, with a specific deny message.
• packages/core/src/policy/policies/yolo.toml
  • Added a new rule to deny both enter_plan_mode and exit_plan_mode when the system is in 'yolo' mode.
• packages/core/src/policy/policy-engine.test.ts
  • Added a test case to ensure enter_plan_mode is denied when already in PLAN mode.
  • Added a test case to ensure exit_plan_mode is denied when in DEFAULT mode.
  • Added a test case to ensure both plan tools are denied when in YOLO mode.

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[gemini-code-assist]

Code Review

This pull request refactors the management of plan-related tools (enter_plan_mode and exit_plan_mode) by replacing the imperative syncPlanModeTools method with declarative policy rules. The logic for enabling or disabling these tools based on the current ApprovalMode is now handled by DENY rules in the plan.toml, write.toml, and yolo.toml policy files. The Config class is simplified by removing the manual synchronization logic, and tests have been updated to reflect this new declarative approach. The plan-related tools are now always registered if the feature is enabled, with their visibility controlled by the policy engine.

[github-actions]

Size Change: -1.19 kB (0%)

Total Size: 25.8 MB

Filename	Size	Change
./bundle/gemini.js	25.3 MB	-1.19 kB (0%)

ℹ️ View Unchanged

Filename	Size
./bundle/node_modules/@google/gemini-cli-devtools/dist/client/main.js	221 kB
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/_client-assets.js	227 kB
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/index.js	11.5 kB
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/types.js	132 B
./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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