# AEG-V15-038 — Schedule heartbeat and aging

## Scope

- **WBS ID:** `AEG-V15-038`; **Requirement / API / DB / Job / UI / Test:** `REQ-V15-SCH-06` / `V15-SCH-API` / `MIG-0020` / `J31~J40` / `Cross` / `T-V15-SCH-06`.
- **Dependency / Gate:** `AEG-V15-037` (completed, commit `d38dc32`) / `G3`.
- **Acceptance:** detect a stuck request and produce Owner-alert evidence.

## Source / Assumption / Unknown / Decision Required

- **Source:** `MIG-0020` provides `last_heartbeat_at`; the execution state machine has no heartbeat contract; schedule rows provide Primary/Secondary owners.
- **Assumption:** a heartbeat is valid only for a running execution and cannot move time backwards. Staleness is evaluated against a caller-supplied cutoff, not a hidden default threshold.
- **Unknown:** no approved stale duration, alert transport, severity, or escalation policy exists for J31–J40.
- **Decision Required:** an approved owner-alert contract is required before an I/O alert sender or automatic action may be added. This Slice deliberately creates no default threshold, alert, or schedule activation.

## Actual evidence and remaining acceptance

- `dotnet test tests/KArtSell.ModelOperations.UnitTests/KArtSell.ModelOperations.UnitTests.csproj -c Release --filter FullyQualifiedName~ModelOperationExecutionTests --logger "trx;LogFileName=ModelOperationExecutionHeartbeatTests_20260809.trx" --results-directory evidence/AEG-V15-038`
- Result: passed `5/5`; artifact: `evidence/AEG-V15-038/ModelOperationExecutionHeartbeatTests_20260809.trx`; SHA-256: `2ADBB526FAF6E5D924EB3F53C7E582E736199A59E0DA4E4FD25DCAA82A661BBC`.
- A running execution alone can write a monotonic heartbeat; a caller-provided cutoff deterministically identifies staleness. No magic number, wall clock, alert sender, retry, or activation was introduced.
- **Not complete:** persist heartbeat to `last_heartbeat_at`, query it with schedule owners, and produce Owner-alert evidence after the stale-duration and alert-contract decision is approved.
