> ## Documentation Index
> Fetch the complete documentation index at: https://docs.useharmonia.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# Effect contracts reference

> Commands, authorization, claims, idempotency, and terminal effect outcomes.

`EffectCommand` in `src/lib/effectCommands.ts` is the deterministic execution envelope. It identifies tenant, source, job, action, payload, digest, authorization, optional execution time, and state.

## Authorization

A command is authorized by either an approval record carrying the approved payload digest or a governed mandate carrying its digest and authorized payload digest. Construction fails when the recomputed canonical SHA-256 digest differs.

## Lifecycle

```text theme={"system"}
pending → claimed → applied
                  ↘ failed
                  ↘ uncertain
pending → cancelled
```

Claims lease one attempt and use an idempotency key. An existing applied receipt yields `already_applied`; an expired or ambiguous claim fails closed as uncertain rather than repeating the external effect.

Terminal aggregation is `succeeded`, `partial`, `failed`, or `unresolved`. See [Effect lifecycle](/diagrams/effect-lifecycle) and [Receipts and verification](/reference/receipts-verification).