# Brief: executor-v2-output-contract

## Background

`executor_evidence_v1` still made Chat Executor produce both evidence attribution and final user-facing prose through `diagnosis_summary` and `user_facing_answer`.

This kept Executor in a "diagnose and narrate" role and left room for unsupported conclusions to appear before later verification and composition stages.

## Goal

Narrow Chat Executor output to `executor_evidence_v2`: structured diagnostic material only, with final expression removed from Executor.

## Scope

- Update Chat Executor prompt to emit `executor_evidence_v2`.
- Remove `diagnosis_summary` and `user_facing_answer` from Executor output.
- Keep `claims`, `hypotheses`, `recommended_actions`, `missing_info`, and evidence bindings.
- Add temporary ChatService rendering for PASS + V2 output so normal users do not see raw JSON.
- Preserve V1 `user_facing_answer` extraction for compatibility.

## Non-Goals

- No Gatekeeper implementation.
- No Verifier V2 `claim_checks`.
- No Composer.
- No Planner changes.
- No database schema changes.
- No evidence tool signature changes.

## Related OpenSpec

`openspec/changes/archive/2026-07-07-executor-v2-output-contract/`