Agent Tool Design The Agent Tool Contract — 5 principles for designing tools that agents call reliably. The 5 Principles Principle 1: Predictable Signature Tools must have typed, named parameters with clear required/optional distinction. No positional ambiguity. Good: Bad: Principle 2: Rich Errors Errors must include: error code (machine-readable), message (human-readable), context (debugging data). Good: Bad: Principle 3: Token-Efficient Output Tools return structured minimal data. No prose explanations, no redundant wrapping, no verbose status messages. Agents format output themselves. Good…