# Promotion Gate Ownership Contract

## Purpose

This contract freezes ownership for promotion gate decisions and defines the
Policy-to-Orchestrator interface.

## Ownership Rules

- Policy Engine owns PASS/FAIL gate evaluation semantics.
- Concelier owns advisory ingestion and linkset publication only.
- Release Orchestrator executes promotion state transitions using Policy outputs.
- Authority enforces identity/scope boundaries for all callers.

## Explicit Non-Goals for Concelier

- No PASS/FAIL decisioning for promotion gates.
- No direct production of promotion allow/deny verdicts.
- No mutation of Policy-derived effective findings.

## Policy Evaluation Interface

```json
{
  "request": {
    "tenantId": "string",
    "promotionId": "guid",
    "targetEnvironment": "string",
    "artifactDigest": "sha256:...",
    "evidenceRef": "guid",
    "policyBundleDigest": "sha256:..."
  },
  "response": {
    "decision": "allow|deny|pending",
    "reasonCodes": ["string"],
    "policyDigest": "sha256:...",
    "determinismHash": "sha256:...",
    "evaluatedAtUtc": "2026-02-10T00:00:00Z"
  }
}
```

## Determinism and Fail-Closed Rules

- Identical request payloads must produce identical decision outputs.
- Missing or invalid policy inputs MUST return explicit deny or pending according
  to policy profile; no implicit allow.
- Reason codes must be stable and sortable for replay/audit.

## Required Test Coverage

Promotion/Orchestrator side:
- `src/ReleaseOrchestrator/__Tests/StellaOps.ReleaseOrchestrator.Promotion.Tests/Gate/PolicyGateTests.cs`
- `src/ReleaseOrchestrator/__Tests/StellaOps.ReleaseOrchestrator.Promotion.Tests/Decision/DecisionEngineTests.cs`
- `src/ReleaseOrchestrator/__Tests/StellaOps.ReleaseOrchestrator.Promotion.Tests/Gate/GateEvaluatorTests.cs`

Policy side:
- `src/Policy/__Tests/StellaOps.Policy.Engine.Tests/Gates/PolicyGateEvaluatorTests.cs`
- `src/Policy/__Tests/StellaOps.Policy.Engine.Tests/Determinism/PolicyEngineDeterminismTests.cs`
- `src/Policy/__Tests/StellaOps.Policy.Engine.Tests/Gates/Determinization/DeterminizationGateTests.cs`

## Integration References

- Evidence contract: `docs/modules/evidence-locker/promotion-evidence-contract.md`
- Promotion APIs: `docs/modules/release-jobengine/api/promotions.md`
- Runtime closure plan: `docs/modules/release-jobengine/promotion-runtime-gap-closure-plan.md`