StreamEvent

StreamEvent = { sessionId: string; type: "session:start"; } | { result: RunResult; sessionId: string; type: "session:end"; } | { turnId: string; turnIndex: number; type: "turn:start"; } | { text: string; turnId: string; turnIndex: number; type: "turn:end"; } | { callIndex: number; model: string; type: "model:start"; } | { callIndex: number; text: string; type: "model:chunk"; } | { callIndex: number; finishReason: string; type: "model:end"; } | { args: Record<string, unknown>; callId: string; tool: string; type: "tool:start"; } | { callId: string; result: unknown; tool: string; type: "tool:end"; } | { error: Error; type: "error"; }

Discriminated union of all events emitted during agent execution.

Events follow the lifecycle nesting: session → turn → model/tool. Consumers iterate over these via for await (const event of agent.run(...)).