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

# action_ref (legacy / interop)

> action_ref is the legacy interop primitive, unchanged for existing adopters alongside its hosted verifier. New builds should use execution_ref. Apache 2.0.

<Note>
  The AlgoVoi keystone now leads with [`execution_ref`](/execution-ref), decision-bound
  execution evidence. `action_ref` remains available and **unchanged** for existing adopters
  and for cross-ecosystem interop; new integrations should prefer `execution_ref`.
</Note>

## Aligning with the keystone

The substrate leads with [`execution_ref`](/execution-ref) and the
[keystone](/keystone). `action_ref` is the supported interop primitive the keystone
composes around.

**Existing adopters are not affected.** The `action_ref` preimage, byte output, and
this hosted endpoint are unchanged: the same input gives the same hash it always has
(0.4.0 and 1.0.0 byte-identical). The 1.0.0 release is purely additive, so you can stay
on your current version or upgrade and continue with no changes.

`action_ref` is a content-addressed handle for an agent action:

```
action_ref = "sha256:" + SHA-256(JCS({agent_id, action_type, scope, timestamp_ms}))
```

It is serialised using [RFC 8785 (JCS)](https://www.rfc-editor.org/rfc/rfc8785) with an
integer-millisecond timestamp, reproducible across languages.

The hosted verifier remains live for interop confirmation, no auth required:

```bash theme={null}
POST https://verify.algovoi.co.uk/action-ref
Content-Type: application/json

{ "agent_id": "did:web:api.algovoi.co.uk", "action_type": "payment.authorize",
  "scope": "base:0x2d96f2bc", "timestamp_ms": 1748534400000 }
```

## Moving to execution\_ref

`execution_ref` is not a field-for-field rename: it binds an executed action to the
`decision_ref` that authorized it, proving the execution is consistent with the decision
rather than merely correlated with an identity. See [`execution_ref`](/execution-ref) for
the construction and the full keystone flow. Upgrade to `algovoi-substrate` 1.0.0 and
continue with `action_ref` as is, or adopt `execution_ref` at your own pace; the two
coexist.

## See also

* [`execution_ref`](/execution-ref): the decision-bound execution-evidence primitive
* [Canonicalisation substrate](/canonicalisation-substrate): the JCS discipline
* [Conformance vectors](/conformance-vectors): the cross-implementation matrix