fix(coding-agents): answer tools/list when disabled

[altaywtf]

Summary

Keep opted-out Hindsight MCP servers inert while making their tool-discovery contract valid. This prevents clients that probe tools/list from treating an intentionally disabled project as an MCP startup failure.

Changed

• Build the MCP server through one registration helper.
• When the resolved project exposes no tools, advertise an empty tool capability and answer tools/list with { "tools": [] }.
• Add an in-memory MCP client/server regression test for the zero-tool path.

Risks

Low. Normal tool registration is unchanged; only the existing zero-tool path gains an explicit discovery response.

Verification

• npm test — 530 tests passed.
• npm run build — passed.
• ./scripts/hooks/lint.sh — passed.
• git diff --check upstream/main...HEAD — passed.
• Project code review — no findings.

Complexity

The zero-tool path is constant-time. No API, persistence, or network behavior changes.

[Copilot]

Pull request overview

This PR hardens the hindsight-integrations/coding-agents MCP server’s zero-tool (“opted-out/disabled”) mode so that MCP clients probing tools/list don’t misinterpret an intentionally inert server as a startup failure. It introduces a single helper to build the MCP server surface and adds a regression test to ensure the discovery contract is valid when no tools are exposed.

Changes:

• Centralized MCP server construction into buildMcpServer(...) to consistently register tools (or a valid empty tool surface).
• When the resolved project exposes zero tools, explicitly advertises an empty tools capability and answers tools/list with { tools: [] }.
• Added an in-memory client/server test covering the zero-tool tools/list path.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
hindsight-integrations/coding-agents/src/mcp-server.ts	Adds buildMcpServer and ensures disabled projects still respond to tools/list with an empty tool set.
hindsight-integrations/coding-agents/src/mcp-server.test.ts	Adds an in-memory regression test validating capabilities + tools/list response for the zero-tool server.

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[nicoloboschi]

Rebased onto current main and continued in #3626 — GitHub rejects pushes to this fork branch with a 403 despite maintainer_can_modify: true, so the commit could not be updated in place. Your commit and authorship are preserved there.

The conflicts with main were textual only: #3603 refactored main() onto resolveHostMemory and added resolveHarness after this branch was cut. buildMcpServer and its InMemoryTransport test needed no changes — full suite is 619 passing on the rebase.

Closing in favour of #3626.

[altaywtf]

thanks @nicoloboschi 🙇
think it's because I forked it to org repo rather than personal.
will keep in mind next time. 👍