## Send Events `beta.sessions.events.send(strsession_id, EventSendParams**kwargs) -> BetaManagedAgentsSendSessionEvents` **post** `/v1/sessions/{session_id}/events` Send Events ### Parameters - `session_id: str` - `events: Iterable[BetaManagedAgentsEventParams]` Events to send to the `session`. - `class BetaManagedAgentsUserMessageEventParams: …` Parameters for sending a user message to the session. - `content: List[Content]` Array of content blocks for the user message. - `class BetaManagedAgentsTextBlock: …` Regular text content. - `text: str` The text content. - `type: Literal["text"]` - `"text"` - `class BetaManagedAgentsImageBlock: …` Image content specified directly as base64 data or as a reference via a URL. - `source: Source` Union type for image source variants. - `class BetaManagedAgentsBase64ImageSource: …` Base64-encoded image data. - `data: str` Base64-encoded image data. - `media_type: str` MIME type of the image (e.g., "image/png", "image/jpeg", "image/gif", "image/webp"). - `type: Literal["base64"]` - `"base64"` - `class BetaManagedAgentsURLImageSource: …` Image referenced by URL. - `type: Literal["url"]` - `"url"` - `url: str` URL of the image to fetch. - `class BetaManagedAgentsFileImageSource: …` Image referenced by file ID. - `file_id: str` ID of a previously uploaded file. - `type: Literal["file"]` - `"file"` - `type: Literal["image"]` - `"image"` - `class BetaManagedAgentsDocumentBlock: …` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `source: Source` Union type for document source variants. - `class BetaManagedAgentsBase64DocumentSource: …` Base64-encoded document data. - `data: str` Base64-encoded document data. - `media_type: str` MIME type of the document (e.g., "application/pdf"). - `type: Literal["base64"]` - `"base64"` - `class BetaManagedAgentsPlainTextDocumentSource: …` Plain text document content. - `data: str` The plain text content. - `media_type: Literal["text/plain"]` MIME type of the text content. Must be "text/plain". - `"text/plain"` - `type: Literal["text"]` - `"text"` - `class BetaManagedAgentsURLDocumentSource: …` Document referenced by URL. - `type: Literal["url"]` - `"url"` - `url: str` URL of the document to fetch. - `class BetaManagedAgentsFileDocumentSource: …` Document referenced by file ID. - `file_id: str` ID of a previously uploaded file. - `type: Literal["file"]` - `"file"` - `type: Literal["document"]` - `"document"` - `context: Optional[str]` Additional context about the document for the model. - `title: Optional[str]` The title of the document. - `type: Literal["user.message"]` - `"user.message"` - `class BetaManagedAgentsUserInterruptEventParams: …` Parameters for sending an interrupt to pause the agent. - `type: Literal["user.interrupt"]` - `"user.interrupt"` - `session_thread_id: Optional[str]` 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. - `class BetaManagedAgentsUserToolConfirmationEventParams: …` Parameters for confirming or denying a tool execution request. - `result: Literal["allow", "deny"]` UserToolConfirmationResult enum - `"allow"` - `"deny"` - `tool_use_id: str` 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: Literal["user.tool_confirmation"]` - `"user.tool_confirmation"` - `deny_message: Optional[str]` Optional message providing context for a 'deny' decision. Only allowed when result is 'deny'. - `class BetaManagedAgentsUserCustomToolResultEventParams: …` Parameters for providing the result of a custom tool execution. - `custom_tool_use_id: str` 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: Literal["user.custom_tool_result"]` - `"user.custom_tool_result"` - `content: Optional[List[Content]]` The result content returned by the tool. - `class BetaManagedAgentsTextBlock: …` Regular text content. - `class BetaManagedAgentsImageBlock: …` Image content specified directly as base64 data or as a reference via a URL. - `class BetaManagedAgentsDocumentBlock: …` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `class BetaManagedAgentsSearchResultBlock: …` A block containing a web search result. - `citations: BetaManagedAgentsSearchResultCitations` Citation settings for a search result. - `enabled: bool` Whether citations are enabled for this search result. - `content: List[BetaManagedAgentsSearchResultContent]` Array of text content blocks from the search result. - `text: str` The text content. - `type: Literal["text"]` - `"text"` - `source: str` The URL source of the search result. - `title: str` The title of the search result. - `type: Literal["search_result"]` - `"search_result"` - `is_error: Optional[bool]` Whether the tool execution resulted in an error. - `class BetaManagedAgentsUserDefineOutcomeEventParams: …` Parameters for defining an outcome the agent should work toward. The agent begins work on receipt. - `description: str` What the agent should produce. This is the task specification. - `rubric: Rubric` Rubric for grading the quality of an outcome. - `class BetaManagedAgentsFileRubricParams: …` Rubric referenced by a file uploaded via the Files API. - `file_id: str` ID of the rubric file. - `type: Literal["file"]` - `"file"` - `class BetaManagedAgentsTextRubricParams: …` Rubric content provided inline as text. - `content: str` Rubric content. Plain text or markdown — the grader treats it as freeform text. Maximum 262144 characters. - `type: Literal["text"]` - `"text"` - `type: Literal["user.define_outcome"]` - `"user.define_outcome"` - `max_iterations: Optional[int]` Eval→revision cycles before giving up. Default 3, max 20. - `class BetaManagedAgentsUserToolResultEventParams: …` Parameters for 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. - `tool_use_id: str` 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: Literal["user.tool_result"]` - `"user.tool_result"` - `content: Optional[List[Content]]` The result content returned by the tool. - `class BetaManagedAgentsTextBlock: …` Regular text content. - `class BetaManagedAgentsImageBlock: …` Image content specified directly as base64 data or as a reference via a URL. - `class BetaManagedAgentsDocumentBlock: …` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `class BetaManagedAgentsSearchResultBlock: …` A block containing a web search result. - `is_error: Optional[bool]` Whether the tool execution resulted in an error. - `class BetaManagedAgentsSystemMessageEventParams: …` Privileged context for the accompanying turn and all subsequent turns, appended to the session's system context as a `role: "system"` turn rather than replacing the top-level system prompt. At most one per request: it must be the final event and immediately follow the `user.message`, `user.tool_result`, or `user.custom_tool_result` it accompanies. Only supported on models that accept mid-conversation system messages. - `content: List[BetaManagedAgentsSystemContentBlock]` System content blocks to append. Text-only. - `text: str` The text content. - `type: Literal["text"]` - `"text"` - `type: Literal["system.message"]` - `"system.message"` - `betas: Optional[List[AnthropicBetaParam]]` Optional header to specify the beta version(s) you want to use. - `str` - `Literal["message-batches-2024-09-24", "prompt-caching-2024-07-31", "computer-use-2024-10-22", 25 more]` - `"message-batches-2024-09-24"` - `"prompt-caching-2024-07-31"` - `"computer-use-2024-10-22"` - `"computer-use-2025-01-24"` - `"pdfs-2024-09-25"` - `"token-counting-2024-11-01"` - `"token-efficient-tools-2025-02-19"` - `"output-128k-2025-02-19"` - `"files-api-2025-04-14"` - `"mcp-client-2025-04-04"` - `"mcp-client-2025-11-20"` - `"dev-full-thinking-2025-05-14"` - `"interleaved-thinking-2025-05-14"` - `"code-execution-2025-05-22"` - `"extended-cache-ttl-2025-04-11"` - `"context-1m-2025-08-07"` - `"context-management-2025-06-27"` - `"model-context-window-exceeded-2025-08-26"` - `"skills-2025-10-02"` - `"fast-mode-2026-02-01"` - `"output-300k-2026-03-24"` - `"user-profiles-2026-03-24"` - `"advisor-tool-2026-03-01"` - `"managed-agents-2026-04-01"` - `"cache-diagnosis-2026-04-07"` - `"thinking-token-count-2026-05-13"` - `"server-side-fallback-2026-06-01"` - `"fallback-credit-2026-06-01"` ### Returns - `class BetaManagedAgentsSendSessionEvents: …` Events that were successfully sent to the session. - `data: Optional[List[Data]]` Sent events - `class BetaManagedAgentsUserMessageEvent: …` A user message event in the session conversation. - `id: str` Unique identifier for this event. - `content: List[Content]` Array of content blocks comprising the user message. - `class BetaManagedAgentsTextBlock: …` Regular text content. - `text: str` The text content. - `type: Literal["text"]` - `"text"` - `class BetaManagedAgentsImageBlock: …` Image content specified directly as base64 data or as a reference via a URL. - `source: Source` Union type for image source variants. - `class BetaManagedAgentsBase64ImageSource: …` Base64-encoded image data. - `data: str` Base64-encoded image data. - `media_type: str` MIME type of the image (e.g., "image/png", "image/jpeg", "image/gif", "image/webp"). - `type: Literal["base64"]` - `"base64"` - `class BetaManagedAgentsURLImageSource: …` Image referenced by URL. - `type: Literal["url"]` - `"url"` - `url: str` URL of the image to fetch. - `class BetaManagedAgentsFileImageSource: …` Image referenced by file ID. - `file_id: str` ID of a previously uploaded file. - `type: Literal["file"]` - `"file"` - `type: Literal["image"]` - `"image"` - `class BetaManagedAgentsDocumentBlock: …` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `source: Source` Union type for document source variants. - `class BetaManagedAgentsBase64DocumentSource: …` Base64-encoded document data. - `data: str` Base64-encoded document data. - `media_type: str` MIME type of the document (e.g., "application/pdf"). - `type: Literal["base64"]` - `"base64"` - `class BetaManagedAgentsPlainTextDocumentSource: …` Plain text document content. - `data: str` The plain text content. - `media_type: Literal["text/plain"]` MIME type of the text content. Must be "text/plain". - `"text/plain"` - `type: Literal["text"]` - `"text"` - `class BetaManagedAgentsURLDocumentSource: …` Document referenced by URL. - `type: Literal["url"]` - `"url"` - `url: str` URL of the document to fetch. - `class BetaManagedAgentsFileDocumentSource: …` Document referenced by file ID. - `file_id: str` ID of a previously uploaded file. - `type: Literal["file"]` - `"file"` - `type: Literal["document"]` - `"document"` - `context: Optional[str]` Additional context about the document for the model. - `title: Optional[str]` The title of the document. - `type: Literal["user.message"]` - `"user.message"` - `processed_at: Optional[datetime]` A timestamp in RFC 3339 format - `class BetaManagedAgentsUserInterruptEvent: …` An interrupt event that pauses agent execution and returns control to the user. - `id: str` Unique identifier for this event. - `type: Literal["user.interrupt"]` - `"user.interrupt"` - `processed_at: Optional[datetime]` A timestamp in RFC 3339 format - `session_thread_id: Optional[str]` 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. - `class BetaManagedAgentsUserToolConfirmationEvent: …` A tool confirmation event that approves or denies a pending tool execution. - `id: str` Unique identifier for this event. - `result: Literal["allow", "deny"]` UserToolConfirmationResult enum - `"allow"` - `"deny"` - `tool_use_id: str` 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: Literal["user.tool_confirmation"]` - `"user.tool_confirmation"` - `deny_message: Optional[str]` Optional message providing context for a 'deny' decision. Only allowed when result is 'deny'. - `processed_at: Optional[datetime]` A timestamp in RFC 3339 format - `session_thread_id: Optional[str]` 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. - `class BetaManagedAgentsUserCustomToolResultEvent: …` Event sent by the client providing the result of a custom tool execution. - `id: str` Unique identifier for this event. - `custom_tool_use_id: str` 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: Literal["user.custom_tool_result"]` - `"user.custom_tool_result"` - `content: Optional[List[Content]]` The result content returned by the tool. - `class BetaManagedAgentsTextBlock: …` Regular text content. - `class BetaManagedAgentsImageBlock: …` Image content specified directly as base64 data or as a reference via a URL. - `class BetaManagedAgentsDocumentBlock: …` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `class BetaManagedAgentsSearchResultBlock: …` A block containing a web search result. - `citations: BetaManagedAgentsSearchResultCitations` Citation settings for a search result. - `enabled: bool` Whether citations are enabled for this search result. - `content: List[BetaManagedAgentsSearchResultContent]` Array of text content blocks from the search result. - `text: str` The text content. - `type: Literal["text"]` - `"text"` - `source: str` The URL source of the search result. - `title: str` The title of the search result. - `type: Literal["search_result"]` - `"search_result"` - `is_error: Optional[bool]` Whether the tool execution resulted in an error. - `processed_at: Optional[datetime]` A timestamp in RFC 3339 format - `session_thread_id: Optional[str]` Routes this result to a subagent thread. Copy from the `agent.custom_tool_use` event's `session_thread_id`. - `class BetaManagedAgentsUserDefineOutcomeEvent: …` Echo of a `user.define_outcome` input event. Carries the server-generated `outcome_id` that subsequent `span.outcome_evaluation_*` events reference. - `id: str` Unique identifier for this event. - `description: str` What the agent should produce. Copied from the input event. - `max_iterations: Optional[int]` Evaluate-then-revise cycles before giving up. Default 3, max 20. - `outcome_id: str` Server-generated `outc_` ID for this outcome. Referenced by `span.outcome_evaluation_*` events and the session's `outcome_evaluations` list. - `processed_at: datetime` A timestamp in RFC 3339 format - `rubric: Rubric` Rubric for grading the quality of an outcome. - `class BetaManagedAgentsFileRubric: …` Rubric referenced by a file uploaded via the Files API. - `file_id: str` ID of the rubric file. - `type: Literal["file"]` - `"file"` - `class BetaManagedAgentsTextRubric: …` Rubric content provided inline as text. - `content: str` Rubric content. Plain text or markdown — the grader treats it as freeform text. - `type: Literal["text"]` - `"text"` - `type: Literal["user.define_outcome"]` - `"user.define_outcome"` - `class BetaManagedAgentsUserToolResultEvent: …` 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: str` Unique identifier for this event. - `tool_use_id: str` 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: Literal["user.tool_result"]` - `"user.tool_result"` - `content: Optional[List[Content]]` The result content returned by the tool. - `class BetaManagedAgentsTextBlock: …` Regular text content. - `class BetaManagedAgentsImageBlock: …` Image content specified directly as base64 data or as a reference via a URL. - `class BetaManagedAgentsDocumentBlock: …` Document content, either specified directly as base64 data, as text, or as a reference via a URL. - `class BetaManagedAgentsSearchResultBlock: …` A block containing a web search result. - `is_error: Optional[bool]` Whether the tool execution resulted in an error. - `processed_at: Optional[datetime]` A timestamp in RFC 3339 format - `session_thread_id: Optional[str]` Routes this result to a subagent thread. Copy from the `agent.tool_use` event's `session_thread_id`. - `class BetaManagedAgentsSystemMessageEvent: …` A mid-conversation system message event. Carries system-role content that is appended to the session as a `role: "system"` turn. - `id: str` Unique identifier for this event. - `content: List[BetaManagedAgentsSystemContentBlock]` System content blocks. Text-only. - `text: str` The text content. - `type: Literal["text"]` - `"text"` - `type: Literal["system.message"]` - `"system.message"` - `processed_at: Optional[datetime]` A timestamp in RFC 3339 format ### Example ```python import os from anthropic import Anthropic client = Anthropic( api_key=os.environ.get("ANTHROPIC_API_KEY"), # This is the default and can be omitted ) beta_managed_agents_send_session_events = client.beta.sessions.events.send( session_id="sesn_011CZkZAtmR3yMPDzynEDxu7", events=[{ "content": [{ "text": "Where is my order #1234?", "type": "text", }], "type": "user.message", }], ) print(beta_managed_agents_send_session_events.data) ``` #### 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" } ] } ```