feat(decopilot): add tool_search built-in tool

[tlgimenes]

What is this contribution about?

Implements tool_search, a new built-in tool for decopilot agents to discover available tools in their current execution context.

Key features:

• Simple server-side tool that queries the MCP client's listTools() method
• Optional query parameter for substring filtering on tool names and descriptions
• Returns tool metadata (name, description) with total count
• Includes tool annotations (readOnlyHint, destructiveHint, etc.) and latency tracking
• ~100 lines of implementation following the simplified architecture (no over-engineering)

Technical approach:

• Reuses the already-created mcpClient from the conversation flow
• Added mcpClient parameter to getBuiltInTools() function
• Follows existing patterns from agent_search and subtask built-in tools
• Full test coverage with 6 unit tests

This addresses the need for agents to introspect their available toolset before attempting to call tools.

Screenshots/Demonstration

N/A - This is a backend tool with no UI changes.

How to Test

1. Run Unit Tests

bun test apps/mesh/src/api/routes/decopilot/built-in-tools/tool-search.test.ts

Expected: All 6 tests pass ✓

2. Test Tool Registration

bun test apps/mesh/src/api/routes/decopilot/built-in-tools/registration.test.ts

Expected: Tests pass, confirming tool_search is registered in getBuiltInTools()

3. Test in Decopilot Conversation (Manual)

1. Start the mesh server: bun run dev
2. Create or open a decopilot conversation with a Virtual MCP agent
3. Call the tool_search tool:
   • Without query: tool_search() - returns all available tools
   • With query: tool_search({ query: "slack" }) - returns tools matching "slack"
4. Verify the response includes:
   • tools array with name and description fields
   • totalFound count
   • Tool metadata annotations in the stream

4. Verify Type Safety

bun run check

Expected: No TypeScript errors

Migration Notes

N/A - No database migrations or configuration changes required.

Review Checklist

• PR title is clear and descriptive
• Changes are tested and working (72 tests passing)
• Documentation is updated (inline code comments and test descriptions)
• No breaking changes (backward compatible - existing tools unaffected)

---

Summary by cubic

Adds tool_search, a built-in tool that lets decopilot agents discover and filter available tools from the MCP client. Also updates planning/review skills with clearer names and a streamlined workflow.

• New Features

  • tool_search: server-side tool querying mcpClient.listTools() with optional substring filter (name/description).
  • Returns tool metadata (name, description) and totalFound; emits annotations and latency.
  • getBuiltInTools now accepts mcpClient; routes pass it through.
  • Tests added (unit + registration) to cover filtering, metadata, and integration.

• Refactors

  • Renamed plan-critique → review-plan and review-critique → review-pr; updated references.
  • Removed plan-with-critique; added plan skill that automatically runs review-plan after creating a plan.

^{Written for commit 9b2b108. Summary will update on new commits.}

[github-actions]

🧪 Benchmark

Should we run the Virtual MCP strategy benchmark for this PR?

React with 👍 to run the benchmark.

Reaction	Action
👍	Run quick benchmark (10 & 128 tools)

Benchmark will run on the next push after you react.

[github-actions]

Release Options

Should a new version be published when this PR is merged?

React with an emoji to vote on the release type:

Reaction	Type	Next Version
👍	Prerelease	2.98.1-alpha.1
🎉	Patch	2.98.1
❤️	Minor	2.99.0
🚀	Major	3.0.0

Current version: 2.98.0

Deployment

• Deploy to production (triggers ArgoCD sync after Docker image is published)

[cubic-dev-ai]

No issues found across 12 files