A local inspector for MCP tool calls, latency, and raw JSON-RPC traffic

Reddit r/AI_Agents 10/03/26, 03:52 AM Tools

mcp debugging ai-agents open-source json-rpc developer-tools observability

Summary

Moka Labs released an open-source local inspector UI for MCP tool calls, letting developers view raw JSON-RPC traffic, tokens, and tool-call waterfalls alongside their chat, and export traces to LangGraph. Run it locally via `npx @mokalabs/sandbox`.

Most agent bugs aren't the LLM—they're broken tool schemas, silent 40s timeouts, or unhandled errors. Built an open-source local UI (Moka) to inspect raw MCP JSON-RPC, tokens, and tool waterfalls side-by-side with your chat, then export straight to LangGraph. Run locally: npx @mokalabs/sandbox (GitHub link in the first comment)

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