# Events ## List Session Thread Events `$ ant beta:sessions:threads:events list` **get** `/v1/sessions/{session_id}/threads/{thread_id}/events` List Session Thread Events ### Parameters - `--session-id: string` Path param: Path parameter session_id - `--thread-id: string` Path param: Path parameter thread_id - `--limit: optional number` Query param: Query parameter for limit - `--page: optional string` Query param: Query parameter for page - `--beta: optional array of AnthropicBeta` Header param: Optional header to specify the beta version(s) you want to use. ### Returns - `BetaManagedAgentsListSessionThreadEvents: object { data, next_page }` Paginated list of events for a single thread within a `session`. - `data: optional array of BetaManagedAgentsSessionEvent` Events for the thread, ordered by `created_at`. - `beta_managed_agents_user_message_event: object { id, content, type, processed_at }` A user message event in the session conversation. - `id: string` Unique identifier for this event. - `content: array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock` Array of content blocks comprising the user message. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `text: string` The text content. - `type: "text"` - `"text"` - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `source: BetaManagedAgentsBase64ImageSource or BetaManagedAgentsURLImageSource or BetaManagedAgentsFileImageSource` Union type for image source variants. - `beta_managed_agents_base64_image_source: object { data, media_type, type }` Base64-encoded image data. - `data: string` Base64-encoded image data. - `media_type: string` MIME type of the image (e.g., "image/png", "image/jpeg", "image/gif", "image/webp"). - `type: "base64"` - `"base64"` - `beta_managed_agents_url_image_source: object { type, url }` Image referenced by URL. - `type: "url"` - `"url"` - `url: string` URL of the image to fetch. - `beta_managed_agents_file_image_source: object { file_id, type }` Image referenced by file ID. - `file_id: string` ID of a previously uploaded file. - `type: "file"` - `"file"` - `type: "image"` - `"image"` - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `source: BetaManagedAgentsBase64DocumentSource or BetaManagedAgentsPlainTextDocumentSource or BetaManagedAgentsURLDocumentSource or BetaManagedAgentsFileDocumentSource` Union type for document source variants. - `beta_managed_agents_base64_document_source: object { data, media_type, type }` Base64-encoded document data. - `data: string` Base64-encoded document data. - `media_type: string` MIME type of the document (e.g., "application/pdf"). - `type: "base64"` - `"base64"` - `beta_managed_agents_plain_text_document_source: object { data, media_type, type }` Plain text document content. - `data: string` The plain text content. - `media_type: "text/plain"` MIME type of the text content. Must be "text/plain". - `"text/plain"` - `type: "text"` - `"text"` - `beta_managed_agents_url_document_source: object { type, url }` Document referenced by URL. - `type: "url"` - `"url"` - `url: string` URL of the document to fetch. - `beta_managed_agents_file_document_source: object { file_id, type }` Document referenced by file ID. - `file_id: string` ID of a previously uploaded file. - `type: "file"` - `"file"` - `type: "document"` - `"document"` - `context: optional string` Additional context about the document for the model. - `title: optional string` The title of the document. - `type: "user.message"` - `"user.message"` - `processed_at: optional string` A timestamp in RFC 3339 format - `beta_managed_agents_user_interrupt_event: object { id, type, processed_at, session_thread_id }` An interrupt event that pauses agent execution and returns control to the user. - `id: string` Unique identifier for this event. - `type: "user.interrupt"` - `"user.interrupt"` - `processed_at: optional string` A timestamp in RFC 3339 format - `session_thread_id: optional 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. - `beta_managed_agents_user_tool_confirmation_event: object { id, result, tool_use_id, 4 more }` A tool confirmation event that approves or denies a pending tool execution. - `id: string` Unique identifier for this event. - `result: "allow" or "deny"` UserToolConfirmationResult enum - `"allow"` - `"deny"` - `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](https://platform.claude.com/docs/en/api/beta/sessions/events/list#beta_managed_agents_session_requires_action.event_ids) `stop_reason.event_ids` field. - `type: "user.tool_confirmation"` - `"user.tool_confirmation"` - `deny_message: optional string` Optional message providing context for a 'deny' decision. Only allowed when result is 'deny'. - `processed_at: optional string` A timestamp in RFC 3339 format - `session_thread_id: optional string` When set, the confirmation routes to this subagent's thread rather than the primary. Echo this from the `session_thread_id` on the `agent.tool_use` or `agent.mcp_tool_use` event that prompted the approval. - `beta_managed_agents_user_custom_tool_result_event: object { id, custom_tool_use_id, type, 4 more }` Event sent by the client providing the result of a custom tool execution. - `id: string` Unique identifier for this event. - `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](https://platform.claude.com/docs/en/api/beta/sessions/events/list#beta_managed_agents_session_requires_action.event_ids) `stop_reason.event_ids` field. - `type: "user.custom_tool_result"` - `"user.custom_tool_result"` - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock` The result content returned by the tool. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `beta_managed_agents_search_result_block: object { citations, content, source, 2 more }` A block containing a web search result. - `citations: object { enabled }` Citation settings for a search result. - `enabled: boolean` Whether citations are enabled for this search result. - `content: array of BetaManagedAgentsSearchResultContent` Array of text content blocks from the search result. - `text: string` The text content. - `type: "text"` - `"text"` - `source: string` The URL source of the search result. - `title: string` The title of the search result. - `type: "search_result"` - `"search_result"` - `is_error: optional boolean` Whether the tool execution resulted in an error. - `processed_at: optional string` A timestamp in RFC 3339 format - `session_thread_id: optional string` Routes this result to a subagent thread. Copy from the `agent.custom_tool_use` event's `session_thread_id`. - `beta_managed_agents_agent_custom_tool_use_event: object { id, input, name, 3 more }` Event emitted when the agent calls a custom tool. The session goes idle until the client sends a `user.custom_tool_result` event with the result. - `id: string` Unique identifier for this event. - `input: map[unknown]` Input parameters for the tool call. - `name: string` Name of the custom tool being called. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.custom_tool_use"` - `"agent.custom_tool_use"` - `session_thread_id: optional string` When set, this event was cross-posted from a subagent's thread to surface its custom tool use on the primary thread's stream. Empty on the thread's own events. Echo this on a `user.custom_tool_result` event to route the result back. - `beta_managed_agents_agent_message_event: object { id, content, processed_at, type }` An agent response event in the session conversation. - `id: string` Unique identifier for this event. - `content: array of BetaManagedAgentsTextBlock` Array of text blocks comprising the agent response. - `text: string` The text content. - `type: "text"` - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.message"` - `"agent.message"` - `beta_managed_agents_agent_thinking_event: object { id, processed_at, type }` Indicates the agent is making forward progress via extended thinking. A progress signal, not a content carrier. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.thinking"` - `"agent.thinking"` - `beta_managed_agents_agent_mcp_tool_use_event: object { id, input, mcp_server_name, 5 more }` Event emitted when the agent invokes a tool provided by an MCP server. - `id: string` Unique identifier for this event. - `input: map[unknown]` Input parameters for the tool call. - `mcp_server_name: string` Name of the MCP server providing the tool. - `name: string` Name of the MCP tool being used. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.mcp_tool_use"` - `"agent.mcp_tool_use"` - `evaluated_permission: optional "allow" or "ask" or "deny"` AgentEvaluatedPermission enum - `"allow"` - `"ask"` - `"deny"` - `session_thread_id: optional string` When set, this event was cross-posted from a subagent's thread to surface its permission request on the primary thread's stream. Empty on the thread's own events. Echo this on a `user.tool_confirmation` event to route the approval back. - `beta_managed_agents_agent_mcp_tool_result_event: object { id, mcp_tool_use_id, processed_at, 3 more }` Event representing the result of an MCP tool execution. - `id: string` Unique identifier for this event. - `mcp_tool_use_id: string` The id of the `agent.mcp_tool_use` event this result corresponds to. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.mcp_tool_result"` - `"agent.mcp_tool_result"` - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock` The result content returned by the tool. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `beta_managed_agents_search_result_block: object { citations, content, source, 2 more }` A block containing a web search result. - `is_error: optional boolean` Whether the tool execution resulted in an error. - `beta_managed_agents_agent_tool_use_event: object { id, input, name, 4 more }` Event emitted when the agent invokes a built-in agent tool. - `id: string` Unique identifier for this event. - `input: map[unknown]` Input parameters for the tool call. - `name: string` Name of the agent tool being used. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.tool_use"` - `"agent.tool_use"` - `evaluated_permission: optional "allow" or "ask" or "deny"` AgentEvaluatedPermission enum - `"allow"` - `"ask"` - `"deny"` - `session_thread_id: optional string` When set, this event was cross-posted from a subagent's thread to surface its permission request on the primary thread's stream. Empty on the thread's own events. Echo this on a `user.tool_confirmation` event to route the approval back. - `beta_managed_agents_agent_tool_result_event: object { id, processed_at, tool_use_id, 3 more }` Event representing the result of an agent tool execution. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `tool_use_id: string` The id of the `agent.tool_use` event this result corresponds to. - `type: "agent.tool_result"` - `"agent.tool_result"` - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock` The result content returned by the tool. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `beta_managed_agents_search_result_block: object { citations, content, source, 2 more }` A block containing a web search result. - `is_error: optional boolean` Whether the tool execution resulted in an error. - `beta_managed_agents_agent_thread_message_received_event: object { id, content, from_session_thread_id, 3 more }` Delivery event written to the target thread's input stream when an agent-to-agent message arrives. - `id: string` Unique identifier for this event. - `content: array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock` Message content blocks. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `from_session_thread_id: string` Public `sthr_` ID of the thread that sent the message. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.thread_message_received"` - `"agent.thread_message_received"` - `from_agent_name: optional string` Name of the callable agent this message came from. Absent when received from the primary agent. - `beta_managed_agents_agent_thread_message_sent_event: object { id, content, processed_at, 3 more }` Observability event emitted to the sender's output stream when an agent-to-agent message is sent. - `id: string` Unique identifier for this event. - `content: array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock` Message content blocks. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `processed_at: string` A timestamp in RFC 3339 format - `to_session_thread_id: string` Public `sthr_` ID of the thread the message was sent to. - `type: "agent.thread_message_sent"` - `"agent.thread_message_sent"` - `to_agent_name: optional string` Name of the callable agent this message was sent to. Absent when sent to the primary agent. - `beta_managed_agents_agent_thread_context_compacted_event: object { id, processed_at, type }` Indicates that context compaction (summarization) occurred during the session. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.thread_context_compacted"` - `"agent.thread_context_compacted"` - `beta_managed_agents_session_error_event: object { id, error, processed_at, type }` An error event indicating a problem occurred during session execution. - `id: string` Unique identifier for this event. - `error: BetaManagedAgentsUnknownError or BetaManagedAgentsModelOverloadedError or BetaManagedAgentsModelRateLimitedError or 4 more` An unknown or unexpected error occurred during session execution. A fallback variant; clients that don't recognize a new error code can match on `retry_status` and `message` alone. - `beta_managed_agents_unknown_error: object { message, retry_status, type }` An unknown or unexpected error occurred during session execution. A fallback variant; clients that don't recognize a new error code can match on `retry_status` and `message` alone. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `type: "retrying"` - `"retrying"` - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `type: "exhausted"` - `"exhausted"` - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "terminal"` - `"terminal"` - `type: "unknown_error"` - `"unknown_error"` - `beta_managed_agents_model_overloaded_error: object { message, retry_status, type }` The model is currently overloaded. Emitted after automatic retries are exhausted. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "model_overloaded_error"` - `"model_overloaded_error"` - `beta_managed_agents_model_rate_limited_error: object { message, retry_status, type }` The model request was rate-limited. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "model_rate_limited_error"` - `"model_rate_limited_error"` - `beta_managed_agents_model_request_failed_error: object { message, retry_status, type }` A model request failed for a reason other than overload or rate-limiting. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "model_request_failed_error"` - `"model_request_failed_error"` - `beta_managed_agents_mcp_connection_failed_error: object { mcp_server_name, message, retry_status, type }` Failed to connect to an MCP server. - `mcp_server_name: string` Name of the MCP server that failed to connect. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "mcp_connection_failed_error"` - `"mcp_connection_failed_error"` - `beta_managed_agents_mcp_authentication_failed_error: object { mcp_server_name, message, retry_status, type }` Authentication to an MCP server failed. - `mcp_server_name: string` Name of the MCP server that failed authentication. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "mcp_authentication_failed_error"` - `"mcp_authentication_failed_error"` - `beta_managed_agents_billing_error: object { message, retry_status, type }` The caller's organization or workspace cannot make model requests — out of credits or spend limit reached. Retrying with the same credentials will not succeed; the caller must resolve the billing state. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "billing_error"` - `"billing_error"` - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.error"` - `"session.error"` - `beta_managed_agents_session_status_rescheduled_event: object { id, processed_at, type }` Indicates the session is recovering from an error state and is rescheduled for execution. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.status_rescheduled"` - `"session.status_rescheduled"` - `beta_managed_agents_session_status_running_event: object { id, processed_at, type }` Indicates the session is actively running and the agent is working. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.status_running"` - `"session.status_running"` - `beta_managed_agents_session_status_idle_event: object { id, processed_at, stop_reason, type }` Indicates the agent has paused and is awaiting user input. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `stop_reason: BetaManagedAgentsSessionEndTurn or BetaManagedAgentsSessionRequiresAction or BetaManagedAgentsSessionRetriesExhausted` The agent completed its turn naturally and is ready for the next user message. - `beta_managed_agents_session_end_turn: object { type }` The agent completed its turn naturally and is ready for the next user message. - `type: "end_turn"` - `"end_turn"` - `beta_managed_agents_session_requires_action: object { event_ids, type }` The agent is idle waiting on one or more blocking user-input events (tool confirmation, custom tool result, etc.). Resolving all of them transitions the session back to running. - `event_ids: array of string` The ids of events the agent is blocked on. Resolving fewer than all re-emits `session.status_idle` with the remainder. - `type: "requires_action"` - `"requires_action"` - `beta_managed_agents_session_retries_exhausted: object { type }` The turn ended because the retry budget was exhausted (`max_iterations` hit or an error escalated to `retry_status: 'exhausted'`). - `type: "retries_exhausted"` - `"retries_exhausted"` - `type: "session.status_idle"` - `"session.status_idle"` - `beta_managed_agents_session_status_terminated_event: object { id, processed_at, type }` Indicates the session has terminated, either due to an error or completion. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.status_terminated"` - `"session.status_terminated"` - `beta_managed_agents_session_thread_created_event: object { id, agent_name, processed_at, 2 more }` Emitted when a subagent is spawned as a new thread. Written to the parent thread's output stream so clients observing the session see child creation. - `id: string` Unique identifier for this event. - `agent_name: string` Name of the callable agent the thread runs. - `processed_at: string` A timestamp in RFC 3339 format - `session_thread_id: string` Public `sthr_` ID of the newly created thread. - `type: "session.thread_created"` - `"session.thread_created"` - `beta_managed_agents_span_outcome_evaluation_start_event: object { id, iteration, outcome_id, 2 more }` Emitted when an outcome evaluation cycle begins. - `id: string` Unique identifier for this event. - `iteration: number` 0-indexed revision cycle. 0 is the first evaluation; 1 is the re-evaluation after the first revision; etc. - `outcome_id: string` The `outc_` ID of the outcome being evaluated. - `processed_at: string` A timestamp in RFC 3339 format - `type: "span.outcome_evaluation_start"` - `"span.outcome_evaluation_start"` - `beta_managed_agents_span_outcome_evaluation_end_event: object { id, explanation, iteration, 6 more }` Emitted when an outcome evaluation cycle completes. Carries the verdict and aggregate token usage. A verdict of `needs_revision` means another evaluation cycle follows; `satisfied`, `max_iterations_reached`, `failed`, or `interrupted` are terminal — no further evaluation cycles follow. - `id: string` Unique identifier for this event. - `explanation: string` Human-readable explanation of the verdict. For `needs_revision`, describes which criteria failed and why. - `iteration: number` 0-indexed revision cycle, matching the corresponding `span.outcome_evaluation_start`. - `outcome_evaluation_start_id: string` The id of the corresponding `span.outcome_evaluation_start` event. - `outcome_id: string` The `outc_` ID of the outcome being evaluated. - `processed_at: string` A timestamp in RFC 3339 format - `result: string` Evaluation verdict. 'satisfied': criteria met, session goes idle. 'needs_revision': criteria not met, another revision cycle follows. 'max_iterations_reached': evaluation budget exhausted with criteria still unmet — one final acknowledgment turn follows before the session goes idle, but no further evaluation runs. 'failed': grader determined the rubric does not apply to the deliverables. 'interrupted': user sent an interrupt while evaluation was in progress. - `type: "span.outcome_evaluation_end"` - `"span.outcome_evaluation_end"` - `usage: object { cache_creation_input_tokens, cache_read_input_tokens, input_tokens, 2 more }` Token usage for a single model request. - `cache_creation_input_tokens: number` Tokens used to create prompt cache in this request. - `cache_read_input_tokens: number` Tokens read from prompt cache in this request. - `input_tokens: number` Input tokens consumed by this request. - `output_tokens: number` Output tokens generated by this request. - `speed: optional "standard" or "fast"` Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time. - `"standard"` - `"fast"` - `beta_managed_agents_span_model_request_start_event: object { id, processed_at, type }` Emitted when a model request is initiated by the agent. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "span.model_request_start"` - `"span.model_request_start"` - `beta_managed_agents_span_model_request_end_event: object { id, is_error, model_request_start_id, 3 more }` Emitted when a model request completes. - `id: string` Unique identifier for this event. - `is_error: boolean` Whether the model request resulted in an error. - `model_request_start_id: string` The id of the corresponding `span.model_request_start` event. - `model_usage: object { cache_creation_input_tokens, cache_read_input_tokens, input_tokens, 2 more }` Token usage for a single model request. - `cache_creation_input_tokens: number` Tokens used to create prompt cache in this request. - `cache_read_input_tokens: number` Tokens read from prompt cache in this request. - `input_tokens: number` Input tokens consumed by this request. - `output_tokens: number` Output tokens generated by this request. - `speed: optional "standard" or "fast"` Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time. - `processed_at: string` A timestamp in RFC 3339 format - `type: "span.model_request_end"` - `"span.model_request_end"` - `beta_managed_agents_span_outcome_evaluation_ongoing_event: object { id, iteration, outcome_id, 2 more }` Periodic heartbeat emitted while an outcome evaluation cycle is in progress. Distinguishes 'evaluation is actively running' from 'evaluation is stuck' between the corresponding `span.outcome_evaluation_start` and `span.outcome_evaluation_end` events. - `id: string` Unique identifier for this event. - `iteration: number` 0-indexed revision cycle, matching the corresponding `span.outcome_evaluation_start`. - `outcome_id: string` The `outc_` ID of the outcome being evaluated. - `processed_at: string` A timestamp in RFC 3339 format - `type: "span.outcome_evaluation_ongoing"` - `"span.outcome_evaluation_ongoing"` - `beta_managed_agents_user_define_outcome_event: object { id, description, max_iterations, 4 more }` Echo of a `user.define_outcome` input event. Carries the server-generated `outcome_id` that subsequent `span.outcome_evaluation_*` events reference. - `id: string` Unique identifier for this event. - `description: string` What the agent should produce. Copied from the input event. - `max_iterations: number` Evaluate-then-revise cycles before giving up. Default 3, max 20. - `outcome_id: string` Server-generated `outc_` ID for this outcome. Referenced by `span.outcome_evaluation_*` events and the session's `outcome_evaluations` list. - `processed_at: string` A timestamp in RFC 3339 format - `rubric: BetaManagedAgentsFileRubric or BetaManagedAgentsTextRubric` Rubric for grading the quality of an outcome. - `beta_managed_agents_file_rubric: object { file_id, type }` Rubric referenced by a file uploaded via the Files API. - `file_id: string` ID of the rubric file. - `type: "file"` - `"file"` - `beta_managed_agents_text_rubric: object { content, type }` Rubric content provided inline as text. - `content: string` Rubric content. Plain text or markdown — the grader treats it as freeform text. - `type: "text"` - `"text"` - `type: "user.define_outcome"` - `"user.define_outcome"` - `beta_managed_agents_session_deleted_event: object { id, processed_at, type }` Emitted when a session has been deleted. Terminates any active event stream — no further events will be emitted for this session. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.deleted"` - `"session.deleted"` - `beta_managed_agents_session_thread_status_running_event: object { id, agent_name, processed_at, 2 more }` A session thread has begun executing. Emitted on the thread's own stream and cross-posted to the primary stream for child threads. - `id: string` Unique identifier for this event. - `agent_name: string` Name of the agent the thread runs. - `processed_at: string` A timestamp in RFC 3339 format - `session_thread_id: string` Public sthr_ ID of the thread that started running. - `type: "session.thread_status_running"` - `"session.thread_status_running"` - `beta_managed_agents_session_thread_status_idle_event: object { id, agent_name, processed_at, 3 more }` A session thread has yielded and is awaiting input. Emitted on the thread's own stream and cross-posted to the primary stream for child threads. - `id: string` Unique identifier for this event. - `agent_name: string` Name of the agent the thread runs. - `processed_at: string` A timestamp in RFC 3339 format - `session_thread_id: string` Public sthr_ ID of the thread that went idle. - `stop_reason: BetaManagedAgentsSessionEndTurn or BetaManagedAgentsSessionRequiresAction or BetaManagedAgentsSessionRetriesExhausted` The agent completed its turn naturally and is ready for the next user message. - `beta_managed_agents_session_end_turn: object { type }` The agent completed its turn naturally and is ready for the next user message. - `beta_managed_agents_session_requires_action: object { event_ids, type }` The agent is idle waiting on one or more blocking user-input events (tool confirmation, custom tool result, etc.). Resolving all of them transitions the session back to running. - `beta_managed_agents_session_retries_exhausted: object { type }` The turn ended because the retry budget was exhausted (`max_iterations` hit or an error escalated to `retry_status: 'exhausted'`). - `type: "session.thread_status_idle"` - `"session.thread_status_idle"` - `beta_managed_agents_session_thread_status_terminated_event: object { id, agent_name, processed_at, 2 more }` A session thread has terminated and will accept no further input. Emitted on the thread's own stream and cross-posted to the primary stream for child threads. - `id: string` Unique identifier for this event. - `agent_name: string` Name of the agent the thread runs. - `processed_at: string` A timestamp in RFC 3339 format - `session_thread_id: string` Public sthr_ ID of the thread that terminated. - `type: "session.thread_status_terminated"` - `"session.thread_status_terminated"` - `beta_managed_agents_user_tool_result_event: object { id, tool_use_id, type, 4 more }` Event sent by the client providing the result of an agent-toolset tool execution. Only valid on `self_hosted` environments, where sandbox-routed tools are executed by the client rather than the server. - `id: string` Unique identifier for this event. - `tool_use_id: string` The id of the `agent.tool_use` event this result corresponds to, which can be found in the last `session.status_idle` [event's](https://platform.claude.com/docs/en/api/beta/sessions/events/list#beta_managed_agents_session_requires_action.event_ids) `stop_reason.event_ids` field. - `type: "user.tool_result"` - `"user.tool_result"` - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock` The result content returned by the tool. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `beta_managed_agents_search_result_block: object { citations, content, source, 2 more }` A block containing a web search result. - `is_error: optional boolean` Whether the tool execution resulted in an error. - `processed_at: optional string` A timestamp in RFC 3339 format - `session_thread_id: optional string` Routes this result to a subagent thread. Copy from the `agent.tool_use` event's `session_thread_id`. - `beta_managed_agents_session_thread_status_rescheduled_event: object { id, agent_name, processed_at, 2 more }` A session thread hit a transient error and is retrying automatically. Emitted on the thread's own stream and cross-posted to the primary stream for child threads. - `id: string` Unique identifier for this event. - `agent_name: string` Name of the agent the thread runs. - `processed_at: string` A timestamp in RFC 3339 format - `session_thread_id: string` Public sthr_ ID of the thread that is retrying. - `type: "session.thread_status_rescheduled"` - `"session.thread_status_rescheduled"` - `beta_managed_agents_session_updated_event: object { id, processed_at, type, 3 more }` Emitted when an UpdateSession request changed at least one field. Carries only the fields that changed; absent fields were not part of the update. The new configuration applies from the next turn. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.updated"` - `"session.updated"` - `agent: optional object { id, description, mcp_servers, 8 more }` Resolved `agent` definition for a `session`. Snapshot of the `agent` at `session` creation time. - `id: string` - `description: string` - `mcp_servers: array of BetaManagedAgentsMCPServerURLDefinition` - `name: string` - `type: "url"` - `"url"` - `url: string` - `model: object { id, speed }` Model identifier and configuration. - `id: "claude-opus-4-8" or "claude-opus-4-7" or "claude-opus-4-6" or 7 more or string` The model that will power your agent. See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options. - `"claude-opus-4-8"` Frontier intelligence for long-running agents and coding - `"claude-opus-4-7"` Frontier intelligence for long-running agents and coding - `"claude-opus-4-6"` Most intelligent model for building agents and coding - `"claude-sonnet-4-6"` Best combination of speed and intelligence - `"claude-haiku-4-5"` Fastest model with near-frontier intelligence - `"claude-haiku-4-5-20251001"` Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Premium model combining maximum intelligence with practical performance - `"claude-opus-4-5-20251101"` Premium model combining maximum intelligence with practical performance - `"claude-sonnet-4-5"` High-performance model for agents and coding - `"claude-sonnet-4-5-20250929"` High-performance model for agents and coding - `speed: optional "standard" or "fast"` Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time. - `"standard"` - `"fast"` - `multiagent: object { agents, type }` Resolved coordinator topology with full agent definitions for each roster member. - `agents: array of BetaManagedAgentsSessionThreadAgent` Full `agent` definitions the coordinator may spawn as session threads. - `id: string` - `description: string` - `mcp_servers: array of BetaManagedAgentsMCPServerURLDefinition` - `name: string` - `type: "url"` - `url: string` - `model: object { id, speed }` Model identifier and configuration. - `id: "claude-opus-4-8" or "claude-opus-4-7" or "claude-opus-4-6" or 7 more or string` The model that will power your agent. See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options. - `speed: optional "standard" or "fast"` Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time. - `name: string` - `skills: array of BetaManagedAgentsAnthropicSkill or BetaManagedAgentsCustomSkill` - `beta_managed_agents_anthropic_skill: object { skill_id, type, version }` A resolved Anthropic-managed skill. - `skill_id: string` - `type: "anthropic"` - `"anthropic"` - `version: string` - `beta_managed_agents_custom_skill: object { skill_id, type, version }` A resolved user-created custom skill. - `skill_id: string` - `type: "custom"` - `"custom"` - `version: string` - `system: string` - `tools: array of BetaManagedAgentsAgentToolset20260401 or BetaManagedAgentsMCPToolset or BetaManagedAgentsCustomTool` - `beta_managed_agents_agent_toolset20260401: object { configs, default_config, type }` - `configs: array of BetaManagedAgentsAgentToolConfig` - `enabled: boolean` - `name: "bash" or "edit" or "read" or 5 more` Built-in agent tool identifier. - `"bash"` - `"edit"` - `"read"` - `"write"` - `"glob"` - `"grep"` - `"web_fetch"` - `"web_search"` - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy` Permission policy for tool execution. - `beta_managed_agents_always_allow_policy: object { type }` Tool calls are automatically approved without user confirmation. - `type: "always_allow"` - `"always_allow"` - `beta_managed_agents_always_ask_policy: object { type }` Tool calls require user confirmation before execution. - `type: "always_ask"` - `"always_ask"` - `default_config: object { enabled, permission_policy }` Resolved default configuration for agent tools. - `enabled: boolean` - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy` Permission policy for tool execution. - `beta_managed_agents_always_allow_policy: object { type }` Tool calls are automatically approved without user confirmation. - `beta_managed_agents_always_ask_policy: object { type }` Tool calls require user confirmation before execution. - `type: "agent_toolset_20260401"` - `"agent_toolset_20260401"` - `beta_managed_agents_mcp_toolset: object { configs, default_config, mcp_server_name, type }` - `configs: array of BetaManagedAgentsMCPToolConfig` - `enabled: boolean` - `name: string` - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy` Permission policy for tool execution. - `beta_managed_agents_always_allow_policy: object { type }` Tool calls are automatically approved without user confirmation. - `beta_managed_agents_always_ask_policy: object { type }` Tool calls require user confirmation before execution. - `default_config: object { enabled, permission_policy }` Resolved default configuration for all tools from an MCP server. - `enabled: boolean` - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy` Permission policy for tool execution. - `beta_managed_agents_always_allow_policy: object { type }` Tool calls are automatically approved without user confirmation. - `beta_managed_agents_always_ask_policy: object { type }` Tool calls require user confirmation before execution. - `mcp_server_name: string` - `type: "mcp_toolset"` - `"mcp_toolset"` - `beta_managed_agents_custom_tool: object { description, input_schema, name, type }` A custom tool as returned in API responses. - `description: string` - `input_schema: object { properties, required, type }` JSON Schema for custom tool input parameters. - `properties: optional map[unknown]` JSON Schema properties defining the tool's input parameters. - `required: optional array of string` List of required property names. - `type: optional "object"` Must be 'object' for tool input schemas. - `"object"` - `name: string` - `type: "custom"` - `"custom"` - `type: "agent"` - `"agent"` - `version: number` - `type: "coordinator"` - `"coordinator"` - `name: string` - `skills: array of BetaManagedAgentsAnthropicSkill or BetaManagedAgentsCustomSkill` - `beta_managed_agents_anthropic_skill: object { skill_id, type, version }` A resolved Anthropic-managed skill. - `beta_managed_agents_custom_skill: object { skill_id, type, version }` A resolved user-created custom skill. - `system: string` - `tools: array of BetaManagedAgentsAgentToolset20260401 or BetaManagedAgentsMCPToolset or BetaManagedAgentsCustomTool` - `beta_managed_agents_agent_toolset20260401: object { configs, default_config, type }` - `beta_managed_agents_mcp_toolset: object { configs, default_config, mcp_server_name, type }` - `beta_managed_agents_custom_tool: object { description, input_schema, name, type }` A custom tool as returned in API responses. - `type: "agent"` - `"agent"` - `version: number` - `metadata: optional map[string]` The session's full metadata bag after the update. Present when the update set non-empty metadata; absent when metadata was unchanged or cleared to empty. - `title: optional string` The session's new title. Present only when the update changed it. - `next_page: optional string` Opaque cursor for the next page. Null when no more results. ### Example ```cli ant beta:sessions:threads:events list \ --api-key my-anthropic-api-key \ --session-id sesn_011CZkZAtmR3yMPDzynEDxu7 \ --thread-id sthr_011CZkZVWa6oIjw0rgXZpnBt ``` #### Response ```json { "data": [ { "id": "sevt_011CZkZGOp0iBcp4kaQSihUmy", "content": [ { "text": "Where is my order #1234?", "type": "text" } ], "type": "user.message", "processed_at": "2026-03-15T10:00:00Z" } ], "next_page": "next_page" } ``` ## Stream Session Thread Events `$ ant beta:sessions:threads:events stream` **get** `/v1/sessions/{session_id}/threads/{thread_id}/stream` Stream Session Thread Events ### Parameters - `--session-id: string` Path param: Path parameter session_id - `--thread-id: string` Path param: Path parameter thread_id - `--beta: optional array of AnthropicBeta` Header param: Optional header to specify the beta version(s) you want to use. ### Returns - `beta_managed_agents_stream_session_thread_events: BetaManagedAgentsUserMessageEvent or BetaManagedAgentsUserInterruptEvent or BetaManagedAgentsUserToolConfirmationEvent or 30 more` Server-sent event in a single thread's stream. - `beta_managed_agents_user_message_event: object { id, content, type, processed_at }` A user message event in the session conversation. - `id: string` Unique identifier for this event. - `content: array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock` Array of content blocks comprising the user message. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `text: string` The text content. - `type: "text"` - `"text"` - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `source: BetaManagedAgentsBase64ImageSource or BetaManagedAgentsURLImageSource or BetaManagedAgentsFileImageSource` Union type for image source variants. - `beta_managed_agents_base64_image_source: object { data, media_type, type }` Base64-encoded image data. - `data: string` Base64-encoded image data. - `media_type: string` MIME type of the image (e.g., "image/png", "image/jpeg", "image/gif", "image/webp"). - `type: "base64"` - `"base64"` - `beta_managed_agents_url_image_source: object { type, url }` Image referenced by URL. - `type: "url"` - `"url"` - `url: string` URL of the image to fetch. - `beta_managed_agents_file_image_source: object { file_id, type }` Image referenced by file ID. - `file_id: string` ID of a previously uploaded file. - `type: "file"` - `"file"` - `type: "image"` - `"image"` - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `source: BetaManagedAgentsBase64DocumentSource or BetaManagedAgentsPlainTextDocumentSource or BetaManagedAgentsURLDocumentSource or BetaManagedAgentsFileDocumentSource` Union type for document source variants. - `beta_managed_agents_base64_document_source: object { data, media_type, type }` Base64-encoded document data. - `data: string` Base64-encoded document data. - `media_type: string` MIME type of the document (e.g., "application/pdf"). - `type: "base64"` - `"base64"` - `beta_managed_agents_plain_text_document_source: object { data, media_type, type }` Plain text document content. - `data: string` The plain text content. - `media_type: "text/plain"` MIME type of the text content. Must be "text/plain". - `"text/plain"` - `type: "text"` - `"text"` - `beta_managed_agents_url_document_source: object { type, url }` Document referenced by URL. - `type: "url"` - `"url"` - `url: string` URL of the document to fetch. - `beta_managed_agents_file_document_source: object { file_id, type }` Document referenced by file ID. - `file_id: string` ID of a previously uploaded file. - `type: "file"` - `"file"` - `type: "document"` - `"document"` - `context: optional string` Additional context about the document for the model. - `title: optional string` The title of the document. - `type: "user.message"` - `"user.message"` - `processed_at: optional string` A timestamp in RFC 3339 format - `beta_managed_agents_user_interrupt_event: object { id, type, processed_at, session_thread_id }` An interrupt event that pauses agent execution and returns control to the user. - `id: string` Unique identifier for this event. - `type: "user.interrupt"` - `"user.interrupt"` - `processed_at: optional string` A timestamp in RFC 3339 format - `session_thread_id: optional 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. - `beta_managed_agents_user_tool_confirmation_event: object { id, result, tool_use_id, 4 more }` A tool confirmation event that approves or denies a pending tool execution. - `id: string` Unique identifier for this event. - `result: "allow" or "deny"` UserToolConfirmationResult enum - `"allow"` - `"deny"` - `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](https://platform.claude.com/docs/en/api/beta/sessions/events/list#beta_managed_agents_session_requires_action.event_ids) `stop_reason.event_ids` field. - `type: "user.tool_confirmation"` - `"user.tool_confirmation"` - `deny_message: optional string` Optional message providing context for a 'deny' decision. Only allowed when result is 'deny'. - `processed_at: optional string` A timestamp in RFC 3339 format - `session_thread_id: optional string` When set, the confirmation routes to this subagent's thread rather than the primary. Echo this from the `session_thread_id` on the `agent.tool_use` or `agent.mcp_tool_use` event that prompted the approval. - `beta_managed_agents_user_custom_tool_result_event: object { id, custom_tool_use_id, type, 4 more }` Event sent by the client providing the result of a custom tool execution. - `id: string` Unique identifier for this event. - `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](https://platform.claude.com/docs/en/api/beta/sessions/events/list#beta_managed_agents_session_requires_action.event_ids) `stop_reason.event_ids` field. - `type: "user.custom_tool_result"` - `"user.custom_tool_result"` - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock` The result content returned by the tool. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `beta_managed_agents_search_result_block: object { citations, content, source, 2 more }` A block containing a web search result. - `citations: object { enabled }` Citation settings for a search result. - `enabled: boolean` Whether citations are enabled for this search result. - `content: array of BetaManagedAgentsSearchResultContent` Array of text content blocks from the search result. - `text: string` The text content. - `type: "text"` - `"text"` - `source: string` The URL source of the search result. - `title: string` The title of the search result. - `type: "search_result"` - `"search_result"` - `is_error: optional boolean` Whether the tool execution resulted in an error. - `processed_at: optional string` A timestamp in RFC 3339 format - `session_thread_id: optional string` Routes this result to a subagent thread. Copy from the `agent.custom_tool_use` event's `session_thread_id`. - `beta_managed_agents_agent_custom_tool_use_event: object { id, input, name, 3 more }` Event emitted when the agent calls a custom tool. The session goes idle until the client sends a `user.custom_tool_result` event with the result. - `id: string` Unique identifier for this event. - `input: map[unknown]` Input parameters for the tool call. - `name: string` Name of the custom tool being called. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.custom_tool_use"` - `"agent.custom_tool_use"` - `session_thread_id: optional string` When set, this event was cross-posted from a subagent's thread to surface its custom tool use on the primary thread's stream. Empty on the thread's own events. Echo this on a `user.custom_tool_result` event to route the result back. - `beta_managed_agents_agent_message_event: object { id, content, processed_at, type }` An agent response event in the session conversation. - `id: string` Unique identifier for this event. - `content: array of BetaManagedAgentsTextBlock` Array of text blocks comprising the agent response. - `text: string` The text content. - `type: "text"` - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.message"` - `"agent.message"` - `beta_managed_agents_agent_thinking_event: object { id, processed_at, type }` Indicates the agent is making forward progress via extended thinking. A progress signal, not a content carrier. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.thinking"` - `"agent.thinking"` - `beta_managed_agents_agent_mcp_tool_use_event: object { id, input, mcp_server_name, 5 more }` Event emitted when the agent invokes a tool provided by an MCP server. - `id: string` Unique identifier for this event. - `input: map[unknown]` Input parameters for the tool call. - `mcp_server_name: string` Name of the MCP server providing the tool. - `name: string` Name of the MCP tool being used. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.mcp_tool_use"` - `"agent.mcp_tool_use"` - `evaluated_permission: optional "allow" or "ask" or "deny"` AgentEvaluatedPermission enum - `"allow"` - `"ask"` - `"deny"` - `session_thread_id: optional string` When set, this event was cross-posted from a subagent's thread to surface its permission request on the primary thread's stream. Empty on the thread's own events. Echo this on a `user.tool_confirmation` event to route the approval back. - `beta_managed_agents_agent_mcp_tool_result_event: object { id, mcp_tool_use_id, processed_at, 3 more }` Event representing the result of an MCP tool execution. - `id: string` Unique identifier for this event. - `mcp_tool_use_id: string` The id of the `agent.mcp_tool_use` event this result corresponds to. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.mcp_tool_result"` - `"agent.mcp_tool_result"` - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock` The result content returned by the tool. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `beta_managed_agents_search_result_block: object { citations, content, source, 2 more }` A block containing a web search result. - `is_error: optional boolean` Whether the tool execution resulted in an error. - `beta_managed_agents_agent_tool_use_event: object { id, input, name, 4 more }` Event emitted when the agent invokes a built-in agent tool. - `id: string` Unique identifier for this event. - `input: map[unknown]` Input parameters for the tool call. - `name: string` Name of the agent tool being used. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.tool_use"` - `"agent.tool_use"` - `evaluated_permission: optional "allow" or "ask" or "deny"` AgentEvaluatedPermission enum - `"allow"` - `"ask"` - `"deny"` - `session_thread_id: optional string` When set, this event was cross-posted from a subagent's thread to surface its permission request on the primary thread's stream. Empty on the thread's own events. Echo this on a `user.tool_confirmation` event to route the approval back. - `beta_managed_agents_agent_tool_result_event: object { id, processed_at, tool_use_id, 3 more }` Event representing the result of an agent tool execution. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `tool_use_id: string` The id of the `agent.tool_use` event this result corresponds to. - `type: "agent.tool_result"` - `"agent.tool_result"` - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock` The result content returned by the tool. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `beta_managed_agents_search_result_block: object { citations, content, source, 2 more }` A block containing a web search result. - `is_error: optional boolean` Whether the tool execution resulted in an error. - `beta_managed_agents_agent_thread_message_received_event: object { id, content, from_session_thread_id, 3 more }` Delivery event written to the target thread's input stream when an agent-to-agent message arrives. - `id: string` Unique identifier for this event. - `content: array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock` Message content blocks. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `from_session_thread_id: string` Public `sthr_` ID of the thread that sent the message. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.thread_message_received"` - `"agent.thread_message_received"` - `from_agent_name: optional string` Name of the callable agent this message came from. Absent when received from the primary agent. - `beta_managed_agents_agent_thread_message_sent_event: object { id, content, processed_at, 3 more }` Observability event emitted to the sender's output stream when an agent-to-agent message is sent. - `id: string` Unique identifier for this event. - `content: array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock` Message content blocks. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `processed_at: string` A timestamp in RFC 3339 format - `to_session_thread_id: string` Public `sthr_` ID of the thread the message was sent to. - `type: "agent.thread_message_sent"` - `"agent.thread_message_sent"` - `to_agent_name: optional string` Name of the callable agent this message was sent to. Absent when sent to the primary agent. - `beta_managed_agents_agent_thread_context_compacted_event: object { id, processed_at, type }` Indicates that context compaction (summarization) occurred during the session. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "agent.thread_context_compacted"` - `"agent.thread_context_compacted"` - `beta_managed_agents_session_error_event: object { id, error, processed_at, type }` An error event indicating a problem occurred during session execution. - `id: string` Unique identifier for this event. - `error: BetaManagedAgentsUnknownError or BetaManagedAgentsModelOverloadedError or BetaManagedAgentsModelRateLimitedError or 4 more` An unknown or unexpected error occurred during session execution. A fallback variant; clients that don't recognize a new error code can match on `retry_status` and `message` alone. - `beta_managed_agents_unknown_error: object { message, retry_status, type }` An unknown or unexpected error occurred during session execution. A fallback variant; clients that don't recognize a new error code can match on `retry_status` and `message` alone. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `type: "retrying"` - `"retrying"` - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `type: "exhausted"` - `"exhausted"` - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "terminal"` - `"terminal"` - `type: "unknown_error"` - `"unknown_error"` - `beta_managed_agents_model_overloaded_error: object { message, retry_status, type }` The model is currently overloaded. Emitted after automatic retries are exhausted. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "model_overloaded_error"` - `"model_overloaded_error"` - `beta_managed_agents_model_rate_limited_error: object { message, retry_status, type }` The model request was rate-limited. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "model_rate_limited_error"` - `"model_rate_limited_error"` - `beta_managed_agents_model_request_failed_error: object { message, retry_status, type }` A model request failed for a reason other than overload or rate-limiting. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "model_request_failed_error"` - `"model_request_failed_error"` - `beta_managed_agents_mcp_connection_failed_error: object { mcp_server_name, message, retry_status, type }` Failed to connect to an MCP server. - `mcp_server_name: string` Name of the MCP server that failed to connect. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "mcp_connection_failed_error"` - `"mcp_connection_failed_error"` - `beta_managed_agents_mcp_authentication_failed_error: object { mcp_server_name, message, retry_status, type }` Authentication to an MCP server failed. - `mcp_server_name: string` Name of the MCP server that failed authentication. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "mcp_authentication_failed_error"` - `"mcp_authentication_failed_error"` - `beta_managed_agents_billing_error: object { message, retry_status, type }` The caller's organization or workspace cannot make model requests — out of credits or spend limit reached. Retrying with the same credentials will not succeed; the caller must resolve the billing state. - `message: string` Human-readable error description. - `retry_status: BetaManagedAgentsRetryStatusRetrying or BetaManagedAgentsRetryStatusExhausted or BetaManagedAgentsRetryStatusTerminal` What the client should do next in response to this error. - `beta_managed_agents_retry_status_retrying: object { type }` The server is retrying automatically. Client should wait; the same error type may fire again as retrying, then once as exhausted when the retry budget runs out. - `beta_managed_agents_retry_status_exhausted: object { type }` This turn is dead; queued inputs are flushed and the session returns to idle. Client may send a new prompt. - `beta_managed_agents_retry_status_terminal: object { type }` The session encountered a terminal error and will transition to `terminated` state. - `type: "billing_error"` - `"billing_error"` - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.error"` - `"session.error"` - `beta_managed_agents_session_status_rescheduled_event: object { id, processed_at, type }` Indicates the session is recovering from an error state and is rescheduled for execution. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.status_rescheduled"` - `"session.status_rescheduled"` - `beta_managed_agents_session_status_running_event: object { id, processed_at, type }` Indicates the session is actively running and the agent is working. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.status_running"` - `"session.status_running"` - `beta_managed_agents_session_status_idle_event: object { id, processed_at, stop_reason, type }` Indicates the agent has paused and is awaiting user input. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `stop_reason: BetaManagedAgentsSessionEndTurn or BetaManagedAgentsSessionRequiresAction or BetaManagedAgentsSessionRetriesExhausted` The agent completed its turn naturally and is ready for the next user message. - `beta_managed_agents_session_end_turn: object { type }` The agent completed its turn naturally and is ready for the next user message. - `type: "end_turn"` - `"end_turn"` - `beta_managed_agents_session_requires_action: object { event_ids, type }` The agent is idle waiting on one or more blocking user-input events (tool confirmation, custom tool result, etc.). Resolving all of them transitions the session back to running. - `event_ids: array of string` The ids of events the agent is blocked on. Resolving fewer than all re-emits `session.status_idle` with the remainder. - `type: "requires_action"` - `"requires_action"` - `beta_managed_agents_session_retries_exhausted: object { type }` The turn ended because the retry budget was exhausted (`max_iterations` hit or an error escalated to `retry_status: 'exhausted'`). - `type: "retries_exhausted"` - `"retries_exhausted"` - `type: "session.status_idle"` - `"session.status_idle"` - `beta_managed_agents_session_status_terminated_event: object { id, processed_at, type }` Indicates the session has terminated, either due to an error or completion. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.status_terminated"` - `"session.status_terminated"` - `beta_managed_agents_session_thread_created_event: object { id, agent_name, processed_at, 2 more }` Emitted when a subagent is spawned as a new thread. Written to the parent thread's output stream so clients observing the session see child creation. - `id: string` Unique identifier for this event. - `agent_name: string` Name of the callable agent the thread runs. - `processed_at: string` A timestamp in RFC 3339 format - `session_thread_id: string` Public `sthr_` ID of the newly created thread. - `type: "session.thread_created"` - `"session.thread_created"` - `beta_managed_agents_span_outcome_evaluation_start_event: object { id, iteration, outcome_id, 2 more }` Emitted when an outcome evaluation cycle begins. - `id: string` Unique identifier for this event. - `iteration: number` 0-indexed revision cycle. 0 is the first evaluation; 1 is the re-evaluation after the first revision; etc. - `outcome_id: string` The `outc_` ID of the outcome being evaluated. - `processed_at: string` A timestamp in RFC 3339 format - `type: "span.outcome_evaluation_start"` - `"span.outcome_evaluation_start"` - `beta_managed_agents_span_outcome_evaluation_end_event: object { id, explanation, iteration, 6 more }` Emitted when an outcome evaluation cycle completes. Carries the verdict and aggregate token usage. A verdict of `needs_revision` means another evaluation cycle follows; `satisfied`, `max_iterations_reached`, `failed`, or `interrupted` are terminal — no further evaluation cycles follow. - `id: string` Unique identifier for this event. - `explanation: string` Human-readable explanation of the verdict. For `needs_revision`, describes which criteria failed and why. - `iteration: number` 0-indexed revision cycle, matching the corresponding `span.outcome_evaluation_start`. - `outcome_evaluation_start_id: string` The id of the corresponding `span.outcome_evaluation_start` event. - `outcome_id: string` The `outc_` ID of the outcome being evaluated. - `processed_at: string` A timestamp in RFC 3339 format - `result: string` Evaluation verdict. 'satisfied': criteria met, session goes idle. 'needs_revision': criteria not met, another revision cycle follows. 'max_iterations_reached': evaluation budget exhausted with criteria still unmet — one final acknowledgment turn follows before the session goes idle, but no further evaluation runs. 'failed': grader determined the rubric does not apply to the deliverables. 'interrupted': user sent an interrupt while evaluation was in progress. - `type: "span.outcome_evaluation_end"` - `"span.outcome_evaluation_end"` - `usage: object { cache_creation_input_tokens, cache_read_input_tokens, input_tokens, 2 more }` Token usage for a single model request. - `cache_creation_input_tokens: number` Tokens used to create prompt cache in this request. - `cache_read_input_tokens: number` Tokens read from prompt cache in this request. - `input_tokens: number` Input tokens consumed by this request. - `output_tokens: number` Output tokens generated by this request. - `speed: optional "standard" or "fast"` Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time. - `"standard"` - `"fast"` - `beta_managed_agents_span_model_request_start_event: object { id, processed_at, type }` Emitted when a model request is initiated by the agent. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "span.model_request_start"` - `"span.model_request_start"` - `beta_managed_agents_span_model_request_end_event: object { id, is_error, model_request_start_id, 3 more }` Emitted when a model request completes. - `id: string` Unique identifier for this event. - `is_error: boolean` Whether the model request resulted in an error. - `model_request_start_id: string` The id of the corresponding `span.model_request_start` event. - `model_usage: object { cache_creation_input_tokens, cache_read_input_tokens, input_tokens, 2 more }` Token usage for a single model request. - `cache_creation_input_tokens: number` Tokens used to create prompt cache in this request. - `cache_read_input_tokens: number` Tokens read from prompt cache in this request. - `input_tokens: number` Input tokens consumed by this request. - `output_tokens: number` Output tokens generated by this request. - `speed: optional "standard" or "fast"` Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time. - `processed_at: string` A timestamp in RFC 3339 format - `type: "span.model_request_end"` - `"span.model_request_end"` - `beta_managed_agents_span_outcome_evaluation_ongoing_event: object { id, iteration, outcome_id, 2 more }` Periodic heartbeat emitted while an outcome evaluation cycle is in progress. Distinguishes 'evaluation is actively running' from 'evaluation is stuck' between the corresponding `span.outcome_evaluation_start` and `span.outcome_evaluation_end` events. - `id: string` Unique identifier for this event. - `iteration: number` 0-indexed revision cycle, matching the corresponding `span.outcome_evaluation_start`. - `outcome_id: string` The `outc_` ID of the outcome being evaluated. - `processed_at: string` A timestamp in RFC 3339 format - `type: "span.outcome_evaluation_ongoing"` - `"span.outcome_evaluation_ongoing"` - `beta_managed_agents_user_define_outcome_event: object { id, description, max_iterations, 4 more }` Echo of a `user.define_outcome` input event. Carries the server-generated `outcome_id` that subsequent `span.outcome_evaluation_*` events reference. - `id: string` Unique identifier for this event. - `description: string` What the agent should produce. Copied from the input event. - `max_iterations: number` Evaluate-then-revise cycles before giving up. Default 3, max 20. - `outcome_id: string` Server-generated `outc_` ID for this outcome. Referenced by `span.outcome_evaluation_*` events and the session's `outcome_evaluations` list. - `processed_at: string` A timestamp in RFC 3339 format - `rubric: BetaManagedAgentsFileRubric or BetaManagedAgentsTextRubric` Rubric for grading the quality of an outcome. - `beta_managed_agents_file_rubric: object { file_id, type }` Rubric referenced by a file uploaded via the Files API. - `file_id: string` ID of the rubric file. - `type: "file"` - `"file"` - `beta_managed_agents_text_rubric: object { content, type }` Rubric content provided inline as text. - `content: string` Rubric content. Plain text or markdown — the grader treats it as freeform text. - `type: "text"` - `"text"` - `type: "user.define_outcome"` - `"user.define_outcome"` - `beta_managed_agents_session_deleted_event: object { id, processed_at, type }` Emitted when a session has been deleted. Terminates any active event stream — no further events will be emitted for this session. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.deleted"` - `"session.deleted"` - `beta_managed_agents_session_thread_status_running_event: object { id, agent_name, processed_at, 2 more }` A session thread has begun executing. Emitted on the thread's own stream and cross-posted to the primary stream for child threads. - `id: string` Unique identifier for this event. - `agent_name: string` Name of the agent the thread runs. - `processed_at: string` A timestamp in RFC 3339 format - `session_thread_id: string` Public sthr_ ID of the thread that started running. - `type: "session.thread_status_running"` - `"session.thread_status_running"` - `beta_managed_agents_session_thread_status_idle_event: object { id, agent_name, processed_at, 3 more }` A session thread has yielded and is awaiting input. Emitted on the thread's own stream and cross-posted to the primary stream for child threads. - `id: string` Unique identifier for this event. - `agent_name: string` Name of the agent the thread runs. - `processed_at: string` A timestamp in RFC 3339 format - `session_thread_id: string` Public sthr_ ID of the thread that went idle. - `stop_reason: BetaManagedAgentsSessionEndTurn or BetaManagedAgentsSessionRequiresAction or BetaManagedAgentsSessionRetriesExhausted` The agent completed its turn naturally and is ready for the next user message. - `beta_managed_agents_session_end_turn: object { type }` The agent completed its turn naturally and is ready for the next user message. - `beta_managed_agents_session_requires_action: object { event_ids, type }` The agent is idle waiting on one or more blocking user-input events (tool confirmation, custom tool result, etc.). Resolving all of them transitions the session back to running. - `beta_managed_agents_session_retries_exhausted: object { type }` The turn ended because the retry budget was exhausted (`max_iterations` hit or an error escalated to `retry_status: 'exhausted'`). - `type: "session.thread_status_idle"` - `"session.thread_status_idle"` - `beta_managed_agents_session_thread_status_terminated_event: object { id, agent_name, processed_at, 2 more }` A session thread has terminated and will accept no further input. Emitted on the thread's own stream and cross-posted to the primary stream for child threads. - `id: string` Unique identifier for this event. - `agent_name: string` Name of the agent the thread runs. - `processed_at: string` A timestamp in RFC 3339 format - `session_thread_id: string` Public sthr_ ID of the thread that terminated. - `type: "session.thread_status_terminated"` - `"session.thread_status_terminated"` - `beta_managed_agents_user_tool_result_event: object { id, tool_use_id, type, 4 more }` Event sent by the client providing the result of an agent-toolset tool execution. Only valid on `self_hosted` environments, where sandbox-routed tools are executed by the client rather than the server. - `id: string` Unique identifier for this event. - `tool_use_id: string` The id of the `agent.tool_use` event this result corresponds to, which can be found in the last `session.status_idle` [event's](https://platform.claude.com/docs/en/api/beta/sessions/events/list#beta_managed_agents_session_requires_action.event_ids) `stop_reason.event_ids` field. - `type: "user.tool_result"` - `"user.tool_result"` - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock` The result content returned by the tool. - `beta_managed_agents_text_block: object { text, type }` Regular text content. - `beta_managed_agents_image_block: object { source, type }` Image content specified directly as base64 data or as a reference via a URL. - `beta_managed_agents_document_block: object { source, type, context, title }` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `beta_managed_agents_search_result_block: object { citations, content, source, 2 more }` A block containing a web search result. - `is_error: optional boolean` Whether the tool execution resulted in an error. - `processed_at: optional string` A timestamp in RFC 3339 format - `session_thread_id: optional string` Routes this result to a subagent thread. Copy from the `agent.tool_use` event's `session_thread_id`. - `beta_managed_agents_session_thread_status_rescheduled_event: object { id, agent_name, processed_at, 2 more }` A session thread hit a transient error and is retrying automatically. Emitted on the thread's own stream and cross-posted to the primary stream for child threads. - `id: string` Unique identifier for this event. - `agent_name: string` Name of the agent the thread runs. - `processed_at: string` A timestamp in RFC 3339 format - `session_thread_id: string` Public sthr_ ID of the thread that is retrying. - `type: "session.thread_status_rescheduled"` - `"session.thread_status_rescheduled"` - `beta_managed_agents_session_updated_event: object { id, processed_at, type, 3 more }` Emitted when an UpdateSession request changed at least one field. Carries only the fields that changed; absent fields were not part of the update. The new configuration applies from the next turn. - `id: string` Unique identifier for this event. - `processed_at: string` A timestamp in RFC 3339 format - `type: "session.updated"` - `"session.updated"` - `agent: optional object { id, description, mcp_servers, 8 more }` Resolved `agent` definition for a `session`. Snapshot of the `agent` at `session` creation time. - `id: string` - `description: string` - `mcp_servers: array of BetaManagedAgentsMCPServerURLDefinition` - `name: string` - `type: "url"` - `"url"` - `url: string` - `model: object { id, speed }` Model identifier and configuration. - `id: "claude-opus-4-8" or "claude-opus-4-7" or "claude-opus-4-6" or 7 more or string` The model that will power your agent. See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options. - `"claude-opus-4-8"` Frontier intelligence for long-running agents and coding - `"claude-opus-4-7"` Frontier intelligence for long-running agents and coding - `"claude-opus-4-6"` Most intelligent model for building agents and coding - `"claude-sonnet-4-6"` Best combination of speed and intelligence - `"claude-haiku-4-5"` Fastest model with near-frontier intelligence - `"claude-haiku-4-5-20251001"` Fastest model with near-frontier intelligence - `"claude-opus-4-5"` Premium model combining maximum intelligence with practical performance - `"claude-opus-4-5-20251101"` Premium model combining maximum intelligence with practical performance - `"claude-sonnet-4-5"` High-performance model for agents and coding - `"claude-sonnet-4-5-20250929"` High-performance model for agents and coding - `speed: optional "standard" or "fast"` Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time. - `"standard"` - `"fast"` - `multiagent: object { agents, type }` Resolved coordinator topology with full agent definitions for each roster member. - `agents: array of BetaManagedAgentsSessionThreadAgent` Full `agent` definitions the coordinator may spawn as session threads. - `id: string` - `description: string` - `mcp_servers: array of BetaManagedAgentsMCPServerURLDefinition` - `name: string` - `type: "url"` - `url: string` - `model: object { id, speed }` Model identifier and configuration. - `id: "claude-opus-4-8" or "claude-opus-4-7" or "claude-opus-4-6" or 7 more or string` The model that will power your agent. See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options. - `speed: optional "standard" or "fast"` Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time. - `name: string` - `skills: array of BetaManagedAgentsAnthropicSkill or BetaManagedAgentsCustomSkill` - `beta_managed_agents_anthropic_skill: object { skill_id, type, version }` A resolved Anthropic-managed skill. - `skill_id: string` - `type: "anthropic"` - `"anthropic"` - `version: string` - `beta_managed_agents_custom_skill: object { skill_id, type, version }` A resolved user-created custom skill. - `skill_id: string` - `type: "custom"` - `"custom"` - `version: string` - `system: string` - `tools: array of BetaManagedAgentsAgentToolset20260401 or BetaManagedAgentsMCPToolset or BetaManagedAgentsCustomTool` - `beta_managed_agents_agent_toolset20260401: object { configs, default_config, type }` - `configs: array of BetaManagedAgentsAgentToolConfig` - `enabled: boolean` - `name: "bash" or "edit" or "read" or 5 more` Built-in agent tool identifier. - `"bash"` - `"edit"` - `"read"` - `"write"` - `"glob"` - `"grep"` - `"web_fetch"` - `"web_search"` - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy` Permission policy for tool execution. - `beta_managed_agents_always_allow_policy: object { type }` Tool calls are automatically approved without user confirmation. - `type: "always_allow"` - `"always_allow"` - `beta_managed_agents_always_ask_policy: object { type }` Tool calls require user confirmation before execution. - `type: "always_ask"` - `"always_ask"` - `default_config: object { enabled, permission_policy }` Resolved default configuration for agent tools. - `enabled: boolean` - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy` Permission policy for tool execution. - `beta_managed_agents_always_allow_policy: object { type }` Tool calls are automatically approved without user confirmation. - `beta_managed_agents_always_ask_policy: object { type }` Tool calls require user confirmation before execution. - `type: "agent_toolset_20260401"` - `"agent_toolset_20260401"` - `beta_managed_agents_mcp_toolset: object { configs, default_config, mcp_server_name, type }` - `configs: array of BetaManagedAgentsMCPToolConfig` - `enabled: boolean` - `name: string` - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy` Permission policy for tool execution. - `beta_managed_agents_always_allow_policy: object { type }` Tool calls are automatically approved without user confirmation. - `beta_managed_agents_always_ask_policy: object { type }` Tool calls require user confirmation before execution. - `default_config: object { enabled, permission_policy }` Resolved default configuration for all tools from an MCP server. - `enabled: boolean` - `permission_policy: BetaManagedAgentsAlwaysAllowPolicy or BetaManagedAgentsAlwaysAskPolicy` Permission policy for tool execution. - `beta_managed_agents_always_allow_policy: object { type }` Tool calls are automatically approved without user confirmation. - `beta_managed_agents_always_ask_policy: object { type }` Tool calls require user confirmation before execution. - `mcp_server_name: string` - `type: "mcp_toolset"` - `"mcp_toolset"` - `beta_managed_agents_custom_tool: object { description, input_schema, name, type }` A custom tool as returned in API responses. - `description: string` - `input_schema: object { properties, required, type }` JSON Schema for custom tool input parameters. - `properties: optional map[unknown]` JSON Schema properties defining the tool's input parameters. - `required: optional array of string` List of required property names. - `type: optional "object"` Must be 'object' for tool input schemas. - `"object"` - `name: string` - `type: "custom"` - `"custom"` - `type: "agent"` - `"agent"` - `version: number` - `type: "coordinator"` - `"coordinator"` - `name: string` - `skills: array of BetaManagedAgentsAnthropicSkill or BetaManagedAgentsCustomSkill` - `beta_managed_agents_anthropic_skill: object { skill_id, type, version }` A resolved Anthropic-managed skill. - `beta_managed_agents_custom_skill: object { skill_id, type, version }` A resolved user-created custom skill. - `system: string` - `tools: array of BetaManagedAgentsAgentToolset20260401 or BetaManagedAgentsMCPToolset or BetaManagedAgentsCustomTool` - `beta_managed_agents_agent_toolset20260401: object { configs, default_config, type }` - `beta_managed_agents_mcp_toolset: object { configs, default_config, mcp_server_name, type }` - `beta_managed_agents_custom_tool: object { description, input_schema, name, type }` A custom tool as returned in API responses. - `type: "agent"` - `"agent"` - `version: number` - `metadata: optional map[string]` The session's full metadata bag after the update. Present when the update set non-empty metadata; absent when metadata was unchanged or cleared to empty. - `title: optional string` The session's new title. Present only when the update changed it. ### Example ```cli ant beta:sessions:threads:events stream \ --api-key my-anthropic-api-key \ --session-id sesn_011CZkZAtmR3yMPDzynEDxu7 \ --thread-id sthr_011CZkZVWa6oIjw0rgXZpnBt ``` #### Response ```json { "id": "sevt_011CZkZGOp0iBcp4kaQSihUmy", "content": [ { "text": "Where is my order #1234?", "type": "text" } ], "type": "user.message", "processed_at": "2026-03-15T10:00:00Z" } ```