# SubagentStartedEvent

Defined in: [packages/ai/src/types.ts:1749](https://github.com/TanStack/ai/blob/main/packages/ai/src/types.ts#L1749)

A child agent started. The later chunks for that child carry the same
`subagentRunId`.

@ag-ui/core provides: `subagentRunId`, `name`, `description?`,
`parentSubagentRunId?`, `parentToolCallId?`, `parentMessageId?`, `metadata?`

## Extends

- `SubagentStartedEvent`