AGUI004

Severity: error · Group: Lifecycle · Checked in: core · Since: 0.x

Message: {type} follows the run's terminal {terminalType}

Spec grounding

The RunStarted and either RunFinished or RunError events are mandatory, forming the boundaries of an agent run.

Source: https://docs.ag-ui.com/concepts/events#lifecycle-events

Example

A violating stream from the corpus (spec/fixtures/invalid/AGUI004-event-after-terminal):

{"type":"RUN_STARTED","threadId":"thread_001","runId":"run_001","timestamp":1755300009000}
{"type":"RUN_FINISHED","threadId":"thread_001","runId":"run_001","outcome":{"type":"success"},"timestamp":1755300009100}
{"type":"TEXT_MESSAGE_START","messageId":"msg_001","role":"assistant","timestamp":1755300009200}

Expected findings:

• error AGUI004 at event 2 — TEXT_MESSAGE_START follows the run's terminal RUN_FINISHED