feat(core): add default execution limits for subagents

[abhipatel12]

Summary

Introduced centralized default execution limits for subagents to prevent infinite loops and hanging processes.

Details

• Added DEFAULT_MAX_TURNS (15) and DEFAULT_MAX_TIME_MINUTES (5) to packages/core/src/agents/types.ts.
• Updated agentLoader.ts to apply these defaults when parsing agent definitions (e.g., from Markdown files).
• Refactored local-executor.ts to use these constants as fallbacks during runtime and updated error reporting to reflect the actual limits hit.
• Updated agentLoader.test.ts to verify the new default behavior.
• Updated docs/core/subagents.md to document the new default values.

Related Issues

Related to improving subagent robustness and observability.

How to Validate

Run the updated tests:
npm test -w @google/gemini-cli-core -- src/agents/agentLoader.test.ts src/agents/local-executor.test.ts

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-code-assist]

Summary of Changes

Hello @abhipatel12, 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 centralizes and applies default execution limits for subagents, specifically for maximum turns and maximum execution time. This enhancement aims to improve the robustness of subagents by preventing infinite loops and prolonged execution, thereby ensuring more predictable and stable agent behavior across the system.

Highlights

• Default Execution Limits: Introduced DEFAULT_MAX_TURNS (15) and DEFAULT_MAX_TIME_MINUTES (5) constants to establish default execution limits for subagents, centralizing these critical values.
• Agent Definition Loading: Implemented the use of these new default limits in agentLoader.ts to ensure subagents loaded from definitions (e.g., Markdown files) automatically inherit these constraints if not explicitly set.
• Runtime Execution and Error Reporting: Refactored local-executor.ts to leverage these default constants as fallbacks during runtime and enhanced error messages to accurately report the specific limits (turns or time) that caused agent termination.
• Testing and Documentation: Updated agentLoader.test.ts to include tests verifying that subagents correctly apply the new default execution limits, and documented the new default values in docs/core/subagents.md for clarity.

Changelog

• docs/core/subagents.md
  • Updated documentation for max_turns and timeout_mins to reflect their new default values of 15 and 5 minutes, respectively.
• packages/core/src/agents/agentLoader.test.ts
  • Imported DEFAULT_MAX_TIME_MINUTES and DEFAULT_MAX_TURNS.
  • Modified a test case to use these default constants for runConfig validation, ensuring default limits are correctly applied.
• packages/core/src/agents/agentLoader.ts
  • Imported DEFAULT_MAX_TURNS and DEFAULT_MAX_TIME_MINUTES.
  • Updated markdownToAgentDefinition to use DEFAULT_MAX_TURNS and DEFAULT_MAX_TIME_MINUTES as fallback values for maxTurns and maxTimeMinutes if not specified in the markdown definition.
• packages/core/src/agents/local-executor.ts
  • Imported DEFAULT_MAX_TURNS and DEFAULT_MAX_TIME_MINUTES.
  • Modified the maxTimeMinutes calculation to use DEFAULT_MAX_TIME_MINUTES as a fallback if not explicitly set in the agent's run configuration.
  • Updated error messages for AgentTerminateMode.TIMEOUT and AgentTerminateMode.MAX_TURNS to dynamically report the actual limits used (either defined or default) when an agent terminates.
  • Modified the checkTerminationConditions method to use DEFAULT_MAX_TURNS as a fallback when evaluating the maxTurns limit.
• packages/core/src/agents/types.ts
  • Added DEFAULT_MAX_TURNS (15) and DEFAULT_MAX_TIME_MINUTES (5) constants to define system-wide default execution limits.
  • Updated the RunConfig interface documentation to clarify that maxTimeMinutes and maxTurns will default to these new constants if not specified.

Activity

• The author has updated relevant documentation to reflect the changes.
• Tests have been added or updated to cover the new functionality, ensuring correctness.
• The changes have been validated on MacOS, confirming functionality on a key platform.

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[gemini-code-assist]

Code Review

This pull request introduces default execution limits for subagents, which is a great step for robustness. The implementation correctly adds default values for max_turns and timeout_mins in the agent loader and documentation. My review focuses on improving the implementation within the local-executor to reduce code duplication and on fixing a type inconsistency in types.ts to make the agent configuration more robust and clear.

[github-actions]

Size Change: +237 B (0%)

Total Size: 23.7 MB

ℹ️ View Unchanged

Filename	Size	Change
./bundle/gemini.js	23.7 MB	+237 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

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