How do I avoid common evaluation failure modes for agent tools?

Focusing on realistic, targeted testing practices is a reliable way to avoid common agent tool evaluation failure modes. Test mixed workloads, simulate real failure scenarios, benchmark against your actual agent use cases, avoid relying solely on vendor demos that omit challenging edge cases, and avoid the common pitfalls of only testing happy paths or benchmarking the wrong layers. A key caveat to remember is not to fixate on surface-level idealized results that don’t reflect real operational needs.