Testing

MCP servers are the tools AI agents rely on. We tested 55 of them with mcp-assert, found 20 bugs across 9 servers, and submitted fix PRs. Grafana and Ant Group merged ours. Three days after launch, Ant Group’s visualization team asked us to integrate mcp-assert into their CI. The most common failure: servers throw unhandled exceptions instead of returning isError, leaving agents unable to recover.

Claude Code agents write code fast. Too fast to catch quality issues in real-time. Here’s how to build validation directly into agent workflows using hooks and team coordination - micro validation after every file write, macro validation before completion, and independent review from validator agents.

Traditional tests check examples you think of. Fuzzing explores millions of combinations you don’t. Coverage-guided fuzzing found two production bugs in goldenthread before release - a UTF-8 corruption issue and a regex escaping bug. Here’s how continuous fuzzing works and how to set it up.

You write a struct with a Write method. Three months later, you discover it implements io.Writer. You never declared this. How did it happen? Exploring Go’s implicit interfaces and the power of accidental implementation.

A complete overview of Rust testing strategies: unit tests, integration tests, property-based testing, snapshot testing, parameterized tests, and doctests. Learn which testing approach fits your needs.

Needed offline GCP Secret Manager testing for CI/CD pipelines. Existing solutions were either too heavy or incomplete. Built a standalone gRPC emulator that works with the official Go SDK–zero credentials, zero network calls, 100% local.