Send Events

Call Create session first and replace the example session ID with its returned ID.

POST /anthropic/v1/sessions/{session_id}/events◐ Partial

Request parameters

session_idstring必填
path: Session ID (path or query parameter).
eventsarray必填
Events to send to the session.

Returns

200

Each user.message accepts exactly one nonempty text block. Replace sesn_123 with your session id. Text user.message, user.interrupt and tool confirmation are supported; other input variants are not. The response acknowledges inputs; read replies from event history or the stream. A user.message sent while the session waits for tool approval is queued: the returned event has processed_at null and runs in order once the approval is resolved.

Errors follow the Claude Managed Agents format — see error codes

Response

HTTP 200

Successful response

application/json

Name	Type	Description
data	array<object>	Sent events
data[].id	string	Unique identifier for this event.
data[].content	array<object>	Array of content blocks comprising the user message. / The result content returned by the tool. / The result content returned by the tool. / System content blocks. Text-only.
data[].type	string
data[].processed_at	null \| string \| string \| null \| string \| null \| string	A timestamp in RFC 3339 format
data[].session_thread_id	null \| string	If absent, interrupts every non-archived thread in a multiagent session (or the primary alone in a single-agent session). If present, interrupts only the named thread. / Set by the server to the subagent thread this confirmation was routed to. Omitted when it was routed to the primary thread. / Set by the server to the subagent thread this result was routed to. Omitted when it was routed to the primary thread. / Set by the server to the subagent thread this result was routed to. Omitted when it was routed to the primary thread.
data[].result	string	UserToolConfirmationResult enum
data[].tool_use_id	string	The id of the `agent.tool_use` or `agent.mcp_tool_use` event this result corresponds to, which can be found in the last `session.status_idle` event's `stop_reason.event_ids` field. / The id of the `agent.tool_use` event this result corresponds to, which can be found in the last `session.status_idle` event's `stop_reason.event_ids` field.
data[].deny_message	null \| string	Optional message providing context for a 'deny' decision. Only allowed when result is 'deny'.
data[].custom_tool_use_id	string	The id of the `agent.custom_tool_use` event this result corresponds to, which can be found in the last `session.status_idle` event's `stop_reason.event_ids` field.
data[].is_error	null \| boolean	Whether the tool execution resulted in an error.
data[].description	string	What the agent should produce. Copied from the input event.
data[].max_iterations	null \| number	Evaluate-then-revise cycles before giving up. Default 3, max 20.
data[].outcome_id	string	Server-generated `outc_` ID for this outcome. Referenced by `span.outcome_evaluation_*` events and the session's `outcome_evaluations` list.
data[].rubric	object	Rubric for grading the quality of an outcome.