Blog
Notes on MCP server testing
Long-form posts on the contract-drift problem, regression CI for MCP, and the patterns behind MCPReplay. Written for the people shipping public MCP servers — solo authors, small teams, and the registry-day crowd.
Posts
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Why your MCP server breaks silently — and the fix
A renamed parameter. A return field that grew. An enum value that quietly went away. Your tests pass, the dev loop is green — and three weeks later a user reports the agent "keeps saying it found nothing." This post is about why that happens, why every MCP server author is exposed to it, and the contract-testing pattern that actually fixes it.