feat(plan): add guidance on iterating on approved plans vs creating new plans

[jerop]

This PR adds a new section to the Plan Mode system prompt that references an existing approved plan if available. It provides instructions for the agent to default to iterating on the existing plan rather than creating a new one, unless explicitly requested by the user.

Since the plan file is already mentioned in the chat history, the prompt focuses on guiding the agent on when to update the existing plan versus creating a new one. We can consider passing the path directly in the future but need to carefully address prompt injection risks.

Closes #18260

[gemini-cli]

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

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[gemini-cli]

Hi there! Thank you for your contribution to Gemini CLI.

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[gemini-code-assist]

Summary of Changes

Hello @jerop, 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 introduces a significant enhancement to the agent's 'Plan Mode' by integrating an 'Approved Plan' section into its system prompt. This modification aims to improve the efficiency and consistency of the planning workflow by guiding the agent to leverage and refine existing approved plans, thereby reducing redundant planning efforts and promoting an iterative development approach.

Highlights

• Enhanced Plan Mode Prompt: The system prompt for 'Plan Mode' now includes an 'Approved Plan' section.
• Iterative Planning Guidance: This new section instructs the agent to default to iterating on an existing approved plan, if available, rather than creating a new one.
• Configuration Integration: The 'approvedPlanPath' is now passed from the configuration through the 'PromptProvider' to the prompt rendering logic.
• Codebase Updates: 'PlanningWorkflowOptions' and 'renderPlanningWorkflow' in 'snippets.ts' were modified to support the new 'approvedPlanPath'.
• Test Coverage: New unit tests and updated snapshots ensure the correct generation of the system prompt based on the presence or absence of an approved plan.

Changelog

• packages/core/src/core/snapshots/prompts.test.ts.snap
  • Updated to include new snapshot tests for the 'Approved Plan' section in the Plan Mode system prompt, covering cases where a plan path is provided and when it is not.
• packages/core/src/core/prompts.test.ts
  • Added new test suite for 'Approved Plan in Plan Mode' to verify the conditional rendering of the approved plan section within the system prompt.
  • Mocked 'getApprovedPlanPath' in the config for testing purposes.
• packages/core/src/prompts/promptProvider.ts
  • Modified the 'PromptProvider' to retrieve the 'approvedPlanPath' from the 'config' object and pass it as an option to the 'renderPlanningWorkflow' function.
• packages/core/src/prompts/snippets.ts
  • Updated the 'PlanningWorkflowOptions' interface to include an optional 'approvedPlanPath' property.
  • The 'renderPlanningWorkflow' function was modified to conditionally inject the 'Approved Plan' instructions into the system prompt based on the presence of 'approvedPlanPath'.

Activity

• New feature implementation to enhance agent planning capabilities.
• Updates to core prompt generation logic.
• Addition of new unit tests to validate prompt behavior.
• Snapshot updates reflecting changes in system prompt content.

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[gemini-code-assist]

Code Review

This pull request adds a new 'Approved Plan' section to the Plan Mode system prompt. A security concern exists where approvedPlanPath is interpolated directly, creating a prompt injection vulnerability if it contains backticks, which violates the guideline to avoid including user-provided input directly in LLM content. Additionally, the template's conditional logic for newlines could be improved for robustness, aligning with best practices for template literal management.

[github-actions]

Size Change: +774 B (0%)

Total Size: 23.7 MB

ℹ️ View Unchanged

Filename	Size	Change
./bundle/gemini.js	23.7 MB	+774 B (0%)
./bundle/sandbox-macos-permissive-closed.sb	1.03 kB	0 B
./bundle/sandbox-macos-permissive-open.sb	890 B	0 B
./bundle/sandbox-macos-permissive-proxied.sb	1.31 kB	0 B
./bundle/sandbox-macos-restrictive-closed.sb	3.29 kB	0 B
./bundle/sandbox-macos-restrictive-open.sb	3.36 kB	0 B
./bundle/sandbox-macos-restrictive-proxied.sb	3.56 kB	0 B

_{compressed-size-action}

[jerop]

/gemini review

[gemini-code-assist]

Code Review

This pull request adds a new 'Approved Plan' section to the Plan Mode system prompt. This section is conditionally included when an approved plan is available, instructing the agent to iterate on the existing plan by default. The implementation is clean, using a dedicated function to render the new prompt section, and is accompanied by comprehensive snapshot tests.

The changes look solid and align with the goal of guiding the agent's behavior in Plan Mode. The critical comment regarding a missing dependency needs to be addressed for this PR to be mergeable.