skills/incrementality-design/references/output-contract.md

# Output contract

Return these sections when material to the request

1. **Decision**: the recommended incrementality design
2. **Evidence**: facts used, with assumptions and unknowns separated
3. **Why**: mechanism and decision criteria
4. **Rejected alternative**: the strongest competing option and why it lost
5. **Execution boundary**: what this Skill owns and what must be handed off
6. **Measurement**: business outcome, leading signal, and interpretation guardrail
7. **Confidence and reversal evidence**: confidence level and what new evidence would change the decision

Do not manufacture missing evidence to make the format look complete