# Brief: executor-evidence-output-contract

## Summary

Executor currently returns natural-language diagnosis answers that may mix confirmed evidence, runbook guidance, historical patterns, and unsupported inference. Verifier catches many unsupported facts, but only after extracting claims from prose.

This project defines a structured Executor evidence-attribution contract and updates the Verifier input/verification path to consume it.

## Goal

Make Chat Executor output machine-checkable so confirmed claims are explicitly bound to current-session evidence, while hypotheses and evidence gaps remain visibly separate.

## Scope

- Chat Executor prompt contract.
- Executor structured output parsing.
- Verifier payload extension.
- Chat Verifier prompt behavior.
- Focused tests/eval fixtures.

## Related OpenSpec

`openspec/changes/executor-evidence-output-contract/`