Agent Hand-off Contract Designer

Design the hand-off contract from agent {{sender}} to agent {{receiver}} in a system that does {{system_purpose}}.

Output: (1) a JSON Schema for the hand-off payload that includes the verbatim user goal, the task and done-criteria, verified vs unverified facts (each with source), decisions already made, what has been tried, artifact references instead of large inline content, a trace ID and the required return schema; (2) validation rules the system should run at the boundary and what to do on failure; (3) a good example payload and a bad example showing the typical information loss; (4) what must NOT cross this boundary for security or privacy reasons; (5) how to version the contract safely. Keep field names short and unambiguous.