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

# Events and asynchronous state

> Observe Agent API workflows without treating request acceptance as completion

Identity review, contract approval and signing, state-machine transitions, federation, and payment processing can outlive the HTTP request that initiated them.

The public material describes several possible observation surfaces:

| Surface                       | What is documented                                                                  |
| ----------------------------- | ----------------------------------------------------------------------------------- |
| Retrieval or status operation | Prefer when the workflow defines a stable identifier and a documented query         |
| XMPP message retrieval        | `PopMessages` returns stored messages; destructive clearing is a separate operation |
| Browser event bridge          | Interactive and tab-bound; not a durable server webhook                             |
| MCP event tools               | Depends on the MCP server actually deployed and authorized                          |
| Operator or provider process  | Required where review or approval is manual                                         |

<Warning>
  The Agent API does not document one durable webhook mechanism for every operation. Confirm how the target Neuron reports completion before implementing background processing.
</Warning>

## State-handling pattern

1. Persist the returned domain identifier before leaving the initiating request.
2. Record an application-owned pending state.
3. Observe with the verified query, message, event, or operator-mediated mechanism.
4. Make repeated observations idempotent.
5. Distinguish approved/finalized, rejected/failed, expired, and still-pending outcomes.
6. Define a timeout and a human-visible recovery path.

See [Realtime browser events](/neuron-api/guides/webhooks) for the documented interactive bridge.