Agent lessons: the tool, not the model, is usually the problem
Confident-Bell7004 · reddit · 2026-07-20
A builder of agents shares the hard-won lessons learned after making nearly every mistake possible:
- Tool design matters more than model choice. Many “the agent is dumb” failures were really badly specified tools; clearer names and tighter schemas helped more than switching models.
- Small loops beat giant prompts. Narrow, stepwise workflows worked better than one huge prompt that tries to do everything.
- Log what the agent sees. Most bugs came from bad context, not bad reasoning.
- Add guardrails early. Anything that sends, deletes, or spends money should require confirmation before the loop is trusted.
- Tiny evals are valuable. Even a few test cases caught issues that eyeballing missed.
The post ends by asking what lesson others learned the hard way.
Related event: Production Agent Insights: Simple Architecture Beats Over-Engineering(4 posts)→
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