MCPSpec
Ship reliable MCP servers without writing test code
Details
- External ID
- 47152493
- Source
- HN
- Company
- —
- Product
- MCPSpec
- Website domain
- github.io
- Launched
- Feb. 25, 2026
- Cohort
- —
- Upvotes
- 7
- Upvotes percentile
- 0.38207547169811323
- Tags
- —
- Fetched at
- Sept. 7, 2026, 9:25 p.m.
- Updated at
- Sept. 7, 2026, 9:25 p.m.
Description
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 regressions2. Generate a standalone .js mock from any recording — no API keys, no live server needed in CI3. 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 security5. One command to generate GitHub Actions / GitLab CI configsNo 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.
Enrichment
- Theme
- Model Context Protocol developer tools
- Vertical
- Horizontal
- Function
- Dev tools
- Audience
- Developer
- AI stance
- Not AI
- Project type
- Commercial product
- Normalized one-liner
- testing framework for mcp servers
- Manually corrected
- False
Could you build this?
Yes MCPSpec is a CLI testing and mocking tool that communicates via the Model Context Protocol (JSON-RPC over stdio/SSE), running schema validation, recording responses, and asserting YAML rules.
Discussion
2 comments analyzed.
Competitors mentioned: MCP Inspector (Anthropic), MCP-Scan (Snyk), Promptfoo, MCP Protocol Validator
Concerns raised: No industry standards exist yet for MCP testing/compliance, Market still early, standards development just starting
Competitors
Other products that read as similar to this one — 184 launches clear the similarity bar, closest 8 shown.
Attention rank: #115 of 185 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).
Launched 113 days after the earliest competitor.
- Tool for Testing MCP Servers · hn · 2026-01-07 · 5 upvotes · similarity 0.56
- MCP Playground · hn · 2026-03-01 · 7 upvotes · similarity 0.56
- mcp-recorder · hn · 2026-03-06 · 6 upvotes · similarity 0.55
- Mcpscore · hn · 2026-08-04 · 10 upvotes · similarity 0.55
- mcp-audit-tool · github · 2026-09-26 · 120 upvotes · similarity 0.51
- MCPJam · ph · 2026-09-17 · 141 upvotes · similarity 0.49
- prodcheck · ph · 2026-09-12 · 2 upvotes · similarity 0.49
- MCPShip · ph · 2026-09-12 · 3 upvotes · similarity 0.48
Other launches for this product
- No other launches for this product.
Same idea, different domain
Nobody's really built a dev tools tool for Sales yet.