# Executor Verifier Claim Checks

## Background

Stage one moved Chat Executor to `executor_evidence_v2`, and stage two added deterministic Gatekeeper checks before Verifier. After those stages, Verifier still primarily used the legacy `facts_checked` contract and could still treat `executor_final_answer` as a fact source.

That left two risks:

- Verifier could still extract extra confirmed facts from natural-language Executor output.
- Downstream audit and retry consumers could not distinguish V2 claim-level verification from legacy fact checks.

## Goal

Make Verifier V2 claim-oriented:

- verify `executor_structured_output.claims` as the primary target;
- emit `claim_checks` as the authoritative V2 result;
- keep `facts_checked` only as a compatibility projection;
- enforce code-side guardrails so Gatekeeper failures or malformed structured output cannot remain effective `PASS`.

## Scope

- Updated `chat-verifier-prompt.md` to frame verification as claim derivability.
- Extended `ChatService` to parse, normalize, map, and persist `claim_checks`.
- Added effective verdict guardrails for Gatekeeper failure and malformed/missing Executor structured output.
- Updated verifier logging summaries to count `claim_checks`.
- Updated sequential workflow tests to cover claim mapping and downgrade behavior.

## Non-Goals

- No Composer integration in this phase.
- No final-answer material filtering beyond existing templates and temporary V2 renderer.
- No Executor retry behavior change.
- No Gatekeeper rule expansion.
- No database schema migration.

## OpenSpec

- Active change before archive: `openspec/changes/executor-verifier-claim-checks`
- Capability: `chat-verifier-agent`
- Scale: standard