Why agent skills fail in production, and how to eval them properly
_philschmid · x · 2026-07-20
A talk on why vibe-checking agent skills fails in production and how to build reliable automated evals before users uncover the bugs.
Key points covered:
- Vague skill descriptions lead to failures; adding negative test cases helps prevent keyword hijacking from unrelated prompts.
- Skill files over 500 lines start degrading model reasoning.
- The talk also goes into how to design validation so agent behavior is tested systematically instead of relying on ad hoc impressions.
Related event: Why Agent Skills Fail and How to Evaluate Them(2 posts)→
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