fix: MCP standalone shim proxies full server tool set (#234)

[rohitg00]

Summary

• agentmemory mcp capped non-Claude clients (OpenCode, Cursor, Gemini CLI, Cline, …) at the local 7-tool IMPLEMENTED_TOOLS set even when an agentmemory server was reachable. With AGENTMEMORY_TOOLS=all on the server the user expected 51 tools.
• The shim now delegates tools/list to GET /agentmemory/mcp/tools and forwards any non-essential tool to POST /agentmemory/mcp/call when in proxy mode.
• Local InMemoryKV fallback is unchanged — it still implements only the 7 essential tools, with a clearer error for unknown tools when no server is reachable.

Live e2e (server: AGENTMEMORY_TOOLS=all)

Pre-fix:

shim → tools/list  → 4 tools (default), 7 (TOOLS=all)
shim → memory_lesson_save → "Unknown tool"

Post-fix:

shim → tools/list  → 51 tools
shim → memory_lesson_save → lesson lsn_xxx created

Driver script used: stdio JSON-RPC initialize → tools/list → tools/call.

Tests

• test/mcp-standalone-proxy.test.ts — new cases covering proxy-forward of non-essential tools and the no-server failure mode.
• Full suite: 856 passing.

Closes #234.

Summary by CodeRabbit

• New Features

  • Improved tool discovery and support for non-Claude MCP clients through server-side proxying.
  • Unknown tools are now forwarded to the remote server instead of being rejected locally.
  • Enhanced error handling for unreachable servers.

• Tests

  • Added test coverage for remote tool proxy functionality and failure scenarios.

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Project	Deployment	Actions	Updated (UTC)
agentmemory	Ready	Preview, Comment	May 10, 2026 6:03pm

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 0d499717-8d97-424d-943d-106e07969237

📥 Commits

Reviewing files that changed from the base of the PR and between 0322da8 and 683b043.

📒 Files selected for processing (2)

• src/mcp/standalone.ts
• test/mcp-standalone-proxy.test.ts

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📝 Walkthrough

Walkthrough

The pull request extends the MCP standalone server to support tool proxying and remote tool discovery. When running in proxy mode, unknown tools are forwarded to /agentmemory/mcp/call, and the tool list is fetched from /agentmemory/mcp/tools, enabling non-Claude clients to access the full 51-tool surface beyond the 7 locally-implemented tools.

Changes

MCP Proxy Tool Discovery and Calling

Layer / File(s)	Summary
Generic Proxy Forwarding src/mcp/standalone.ts	New handleProxyGeneric function forwards arbitrary tool calls to the remote /agentmemory/mcp/call endpoint and returns remote MCP content or serialized text response.
Tool Call Routing src/mcp/standalone.ts	handleToolCall now attempts remote proxy execution for unknown tools when in proxy mode, including error logging, handle invalidation, and rethrow on failure.
Remote Tool List Discovery src/mcp/standalone.ts	tools/list handler fetches remote tools from /agentmemory/mcp/tools in proxy mode; falls back to local IMPLEMENTED_TOOLS on fetch failure.
Proxy Integration Tests test/mcp-standalone-proxy.test.ts	Two new Vitest cases verify successful forwarding of memory_lesson_save tool and error handling when the remote server is unreachable.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• rohitg00/agentmemory#161: Modifies src/mcp/standalone.ts for proxy-based MCP tool calling and extends related tests.

Poem

🐰 A proxy path for tools untold,
Beyond the seven we once could hold—
Now fifty-one shine bright and clear,
For every client far and near! ✨

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title 'fix: MCP standalone shim proxies full server tool set (#234)' clearly and concisely summarizes the main change: enabling the MCP standalone shim to proxy the full server tool set instead of limiting to 7 tools.
Linked Issues check	✅ Passed	The PR successfully implements all coding requirements from #234: proxies tools/list to GET /agentmemory/mcp/tools in proxy mode, forwards unknown tool calls to POST /agentmemory/mcp/call, maintains local fallback for non-proxy mode, and includes test coverage for proxy and failure scenarios.
Out of Scope Changes check	✅ Passed	All changes in src/mcp/standalone.ts and test/mcp-standalone-proxy.test.ts are directly aligned with the issue #234 objectives of proxying the full server tool set and handling server unreachability.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/234-mcp-shim-proxy-all-tools

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