Tool Output Schema Design: How Your Tool Responses Shape Agent Reasoning
Most teams designing LLM agents spend considerable effort on tool selection and system prompt wording. Almost none of them think carefully about what their tools return. That's a mistake with compounding consequences — because the shape of a tool response determines how well the agent can reason about it, how much context window it consumes, and how often it hallucinates an interpretation the tool never intended.
Tool output schema design is infrastructure, not plumbing. Get it wrong and your agent will fail in ways that look like reasoning problems when they're actually schema problems.
