Show HN: MCPSpec – Ship reliable MCP servers without writing test code (light-handle.github.io)

7 points by warmcat ↗ HN
Hi HN,

I've been building MCPSpec, an open-source CLI for MCP server reliability. Record sessions, generate mock servers, catch Tool Poisoning, and fail your CI build when something's wrong — without writing test code.

There are ways to validate MCP servers today — the MCP Inspector, ad-hoc SDK scripts, unit tests for server internals — but nothing that handles regression detection, security auditing, mock generation, and CI pass/fail checks in one tool. MCPSpec does that:

1. Record a session against your real server, replay it after changes to catch regressions

2. Generate a standalone .js mock from any recording — no API keys, no live server needed in CI

3. Security audit with 8 rules including Tool Poisoning (prompt injection hidden in tool descriptions)

4. 0-100 quality score across documentation, schema quality, error handling, responsiveness, and security

5. One command to generate GitHub Actions / GitLab CI configs

No LLMs in the loop. Deterministic and fast. Ships with 70 ready-to-run tests for 7 popular MCP servers.

GitHub: https://github.com/light-handle/mcpspec Docs: https://light-handle.github.io/mcpspec/

Would love feedback or feature ideas.

2 comments

[ 3.3 ms ] story [ 21.5 ms ] thread
Good way to go. But are there no other projects that have shipped this? Are there any industry standards?