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One change · api

Send Events changed

api/beta/sessions/events/send

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Lines−762removed
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1---
2title: Send Events
3url: https://platform.claude.com/docs/en/api/beta/sessions/events/send
4---
5 
16# Send Events
27 
38**POST** `/v1/sessions/{session_id}/events`
from line 21
1621 
1722 - `string`
1823 
19 - `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 41 more`
24 - `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 42 more`
2025 
2126 - `"message-batches-2024-09-24"`
2227 
from line 69
6469 
6570 - `"user-profiles-2026-08-18"`
6671 
72 - `"user-profiles-2026-09-04"`
73 
6774 - `"advisor-tool-2026-03-01"`
6875 
6976 - `"managed-agents-2026-04-01"`
from line 113
106113 
107114 - `"mid-conversation-system-clear-at-2026-08-21"`
108115 
116- `"anthropic-workspace-id": optional string`
117 
109118## Body parameters
110119 
111120- `events: array of BetaManagedAgentsEventParams`
from line 125
116125 
117126 Parameters for sending a user message to the session.
118127 
128 - `type: "user.message"`
129 
119130 - `content: array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsRedactedBlock`
120131 
121132 Array of content blocks for the user message.
from line 135
124135 
125136 Regular text content.
126137 
138 - `type: "text"`
139 
127140 - `text: string`
128141 
129142 The text content.
from line 143
130143 
131144 minLength: 1
132145 
133 - `type: "text"`
134 
135146 - `BetaManagedAgentsImageBlock object`
136147 
137148 Image content specified directly as base64 data or as a reference via a URL.
138149 
150 - `type: "image"`
151 
139152 - `source: BetaManagedAgentsBase64ImageSource or BetaManagedAgentsURLImageSource or BetaManagedAgentsFileImageSource`
140153 
141154 Union type for image source variants.
from line 157
144157 
145158 Base64-encoded image data.
146159 
160 - `type: "base64"`
161 
147162 - `data: string`
148163 
149164 Base64-encoded image data.
from line 171
156171 
157172 minLength: 1
158173 
159 - `type: "base64"`
160 
161174 - `BetaManagedAgentsURLImageSource object`
162175 
163176 Image referenced by URL.
from line 187
174187 
175188 Image referenced by file ID.
176189 
190 - `type: "file"`
191 
177192 - `file_id: string`
178193 
179194 ID of a previously uploaded file.
from line 195
180195 
181196 minLength: 1
182197 
183 - `type: "file"`
184 
185 - `type: "image"`
186 
187198 - `BetaManagedAgentsDocumentBlock object`
188199 
189200 Document content, either specified directly as base64 data, as text, or as a reference via a URL.
190201 
202 - `type: "document"`
203 
191204 - `source: BetaManagedAgentsBase64DocumentSource or BetaManagedAgentsPlainTextDocumentSource or BetaManagedAgentsURLDocumentSource or BetaManagedAgentsFileDocumentSource`
192205 
193206 Union type for document source variants.
from line 209
196209 
197210 Base64-encoded document data.
198211 
212 - `type: "base64"`
213 
199214 - `data: string`
200215 
201216 Base64-encoded document data.
from line 223
208223 
209224 minLength: 1
210225 
211 - `type: "base64"`
212 
213226 - `BetaManagedAgentsPlainTextDocumentSource object`
214227 
215228 Plain text document content.
216229 
230 - `type: "text"`
231 
217232 - `data: string`
218233 
219234 The plain text content.
from line 239
224239 
225240 MIME type of the text content. Must be "text/plain".
226241 
227 - `type: "text"`
228 
229242 - `BetaManagedAgentsURLDocumentSource object`
230243 
231244 Document referenced by URL.
from line 255
242255 
243256 Document referenced by file ID.
244257 
258 - `type: "file"`
259 
245260 - `file_id: string`
246261 
247262 ID of a previously uploaded file.
from line 263
248263 
249264 minLength: 1
250265 
251 - `type: "file"`
252 
253 - `type: "document"`
254 
255266 - `context: optional string or null`
256267 
257268 Additional context about the document for the model.
from line 277
266277 
267278 - `type: "redacted"`
268279 
269 - `type: "user.message"`
270 
271280 - `BetaManagedAgentsUserInterruptEventParams object`
272281 
273282 Parameters for sending an interrupt to pause the agent.
from line 291
282291 
283292 Parameters for confirming or denying a tool execution request.
284293 
294 - `type: "user.tool_confirmation"`
295 
285296 - `result: "allow" or "deny"`
286297 
287298 UserToolConfirmationResult enum
from line 307
296307 
297308 minLength: 1, maxLength: 128
298309 
299 - `type: "user.tool_confirmation"`
300 
301310 - `deny_message: optional string or null`
302311 
303312 Optional message providing context for a 'deny' decision. Only allowed when result is 'deny'.
from line 317
308317 
309318 Parameters for providing the result of a custom tool execution.
310319 
320 - `type: "user.custom_tool_result"`
321 
311322 - `custom_tool_use_id: string`
312323 
313324 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.
from line 325
314325 
315326 minLength: 1, maxLength: 128
316327 
317 - `type: "user.custom_tool_result"`
318 
319328 - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock`
320329 
321330 The result content returned by the tool.
from line 345
336345 
337346 A block containing a web search result.
338347 
348 - `type: "search_result"`
349 
339350 - `citations: BetaManagedAgentsSearchResultCitations`
340351 
341352 Citation settings for a search result.
from line 359
348359 
349360 Array of text content blocks from the search result.
350361 
362 - `type: "text"`
363 
351364 - `text: string`
352365 
353366 The text content.
from line 367
354367 
355368 minLength: 1
356369 
357 - `type: "text"`
358 
359370 - `source: string`
360371 
361372 The URL source of the search result.
from line 379
368379 
369380 minLength: 1
370381 
371 - `type: "search_result"`
372 
373382 - `is_error: optional boolean or null`
374383 
375384 Whether the tool execution resulted in an error.
from line 387
378387 
379388 Parameters for defining an outcome the agent should work toward. The agent begins work on receipt.
380389 
390 - `type: "user.define_outcome"`
391 
381392 - `description: string`
382393 
383394 What the agent should produce. This is the task specification.
from line 401
390401 
391402 Rubric referenced by a file uploaded via the Files API.
392403 
404 - `type: "file"`
405 
393406 - `file_id: string`
394407 
395408 ID of the rubric file.
396409 
397 - `type: "file"`
398 
399410 - `BetaManagedAgentsTextRubricParams object`
400411 
401412 Rubric content provided inline as text.
402413 
414 - `type: "text"`
415 
403416 - `content: string`
404417 
405418 Rubric content. Plain text or markdown — the grader treats it as freeform text. Maximum 262144 characters.
from line 419
406419 
407420 maxLength: 262144
408421 
409 - `type: "text"`
410 
411 - `type: "user.define_outcome"`
412 
413422 - `max_iterations: optional number or null`
414423 
415424 Eval→revision cycles before giving up. Default 3, max 20.
from line 429
420429 
421430 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.
422431 
432 - `type: "user.tool_result"`
433 
423434 - `tool_use_id: string`
424435 
425436 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.
from line 437
426437 
427438 minLength: 1, maxLength: 128
428439 
429 - `type: "user.tool_result"`
430 
431440 - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock`
432441 
433442 The result content returned by the tool.
from line 465
456465 
457466 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.
458467 
468 - `type: "system.message"`
469 
459470 - `content: array of BetaManagedAgentsSystemContentBlock`
460471 
461472 System content blocks to append. Text-only.
462473 
474 - `type: "text"`
475 
463476 - `text: string`
464477 
465478 The text content.
from line 479
466479 
467480 minLength: 1
468481 
469 - `type: "text"`
470 
471 - `type: "system.message"`
472 
473482## Returns
474483 
475484- `BetaManagedAgentsSendSessionEvents object`
from line 493
484493 
485494 A user message event in the session conversation.
486495 
496 - `type: "user.message"`
497 
487498 - `id: string`
488499 
489500 Unique identifier for this event.
from line 507
496507 
497508 Regular text content.
498509 
510 - `type: "text"`
511 
499512 - `text: string`
500513 
501514 The text content.
from line 515
502515 
503516 minLength: 1
504517 
505 - `type: "text"`
506 
507518 - `BetaManagedAgentsImageBlock object`
508519 
509520 Image content specified directly as base64 data or as a reference via a URL.
510521 
522 - `type: "image"`
523 
511524 - `source: BetaManagedAgentsBase64ImageSource or BetaManagedAgentsURLImageSource or BetaManagedAgentsFileImageSource`
512525 
513526 Union type for image source variants.
from line 529
516529 
517530 Base64-encoded image data.
518531 
532 - `type: "base64"`
533 
519534 - `data: string`
520535 
521536 Base64-encoded image data.
from line 543
528543 
529544 minLength: 1
530545 
531 - `type: "base64"`
532 
533546 - `BetaManagedAgentsURLImageSource object`
534547 
535548 Image referenced by URL.
from line 559
546559 
547560 Image referenced by file ID.
548561 
562 - `type: "file"`
563 
549564 - `file_id: string`
550565 
551566 ID of a previously uploaded file.
from line 567
552567 
553568 minLength: 1
554569 
555 - `type: "file"`
556 
557 - `type: "image"`
558 
559570 - `BetaManagedAgentsDocumentBlock object`
560571 
561572 Document content, either specified directly as base64 data, as text, or as a reference via a URL.
562573 
574 - `type: "document"`
575 
563576 - `source: BetaManagedAgentsBase64DocumentSource or BetaManagedAgentsPlainTextDocumentSource or BetaManagedAgentsURLDocumentSource or BetaManagedAgentsFileDocumentSource`
564577 
565578 Union type for document source variants.
from line 581
568581 
569582 Base64-encoded document data.
570583 
584 - `type: "base64"`
585 
571586 - `data: string`
572587 
573588 Base64-encoded document data.
from line 595
580595 
581596 minLength: 1
582597 
583 - `type: "base64"`
584 
585598 - `BetaManagedAgentsPlainTextDocumentSource object`
586599 
587600 Plain text document content.
588601 
602 - `type: "text"`
603 
589604 - `data: string`
590605 
591606 The plain text content.
from line 611
596611 
597612 MIME type of the text content. Must be "text/plain".
598613 
599 - `type: "text"`
600 
601614 - `BetaManagedAgentsURLDocumentSource object`
602615 
603616 Document referenced by URL.
from line 627
614627 
615628 Document referenced by file ID.
616629 
630 - `type: "file"`
631 
617632 - `file_id: string`
618633 
619634 ID of a previously uploaded file.
from line 635
620635 
621636 minLength: 1
622637 
623 - `type: "file"`
624 
625 - `type: "document"`
626 
627638 - `context: optional string or null`
628639 
629640 Additional context about the document for the model.
from line 649
638649 
639650 - `type: "redacted"`
640651 
641 - `type: "user.message"`
642 
643652 - `processed_at: optional string or null`
644653 
645654 A timestamp in RFC 3339 format
from line 659
650659 
651660 An interrupt event that pauses agent execution and returns control to the user.
652661 
662 - `type: "user.interrupt"`
663 
653664 - `id: string`
654665 
655666 Unique identifier for this event.
656667 
657 - `type: "user.interrupt"`
658 
659668 - `processed_at: optional string or null`
660669 
661670 A timestamp in RFC 3339 format
from line 679
670679 
671680 A tool confirmation event that approves or denies a pending tool execution.
672681 
682 - `type: "user.tool_confirmation"`
683 
673684 - `id: string`
674685 
675686 Unique identifier for this event.
from line 697
686697 
687698 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.
688699 
689 - `type: "user.tool_confirmation"`
690 
691700 - `deny_message: optional string or null`
692701 
693702 Optional message providing context for a 'deny' decision. Only allowed when result is 'deny'.
from line 717
708717 
709718 Event sent by the client providing the result of a custom tool execution.
710719 
720 - `type: "user.custom_tool_result"`
721 
711722 - `id: string`
712723 
713724 Unique identifier for this event.
from line 727
716727 
717728 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.
718729 
719 - `type: "user.custom_tool_result"`
720 
721730 - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock`
722731 
723732 The result content returned by the tool.
from line 747
738747 
739748 A block containing a web search result.
740749 
750 - `type: "search_result"`
751 
741752 - `citations: BetaManagedAgentsSearchResultCitations`
742753 
743754 Citation settings for a search result.
from line 761
750761 
751762 Array of text content blocks from the search result.
752763 
764 - `type: "text"`
765 
753766 - `text: string`
754767 
755768 The text content.
from line 769
756769 
757770 minLength: 1
758771 
759 - `type: "text"`
760 
761772 - `source: string`
762773 
763774 The URL source of the search result.
from line 781
770781 
771782 minLength: 1
772783 
773 - `type: "search_result"`
774 
775784 - `is_error: optional boolean or null`
776785 
777786 Whether the tool execution resulted in an error.
from line 799
790799 
791800 Echo of a `user.define_outcome` input event. Carries the server-generated `outcome_id` that subsequent `span.outcome_evaluation_*` events reference.
792801 
802 - `type: "user.define_outcome"`
803 
793804 - `id: string`
794805 
795806 Unique identifier for this event.
from line 833
822833 
823834 Rubric referenced by a file uploaded via the Files API.
824835 
836 - `type: "file"`
837 
825838 - `file_id: string`
826839 
827840 ID of the rubric file.
828841 
829 - `type: "file"`
830 
831842 - `BetaManagedAgentsTextRubric object`
832843 
833844 Rubric content provided inline as text.
834845 
846 - `type: "text"`
847 
835848 - `content: string`
836849 
837850 Rubric content. Plain text or markdown — the grader treats it as freeform text.
838851 
839 - `type: "text"`
840 
841 - `type: "user.define_outcome"`
842 
843852 - `BetaManagedAgentsUserToolResultEvent object`
844853 
845854 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.
846855 
856 - `type: "user.tool_result"`
857 
847858 - `id: string`
848859 
849860 Unique identifier for this event.
from line 863
852863 
853864 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.
854865 
855 - `type: "user.tool_result"`
856 
857866 - `content: optional array of BetaManagedAgentsTextBlock or BetaManagedAgentsImageBlock or BetaManagedAgentsDocumentBlock or BetaManagedAgentsSearchResultBlock`
858867 
859868 The result content returned by the tool.
from line 901
892901 
893902 A mid-conversation system message event. Carries system-role content that is appended to the session as a `role: "system"` turn.
894903 
904 - `type: "system.message"`
905 
895906 - `id: string`
896907 
897908 Unique identifier for this event.
from line 911
900911 
901912 System content blocks. Text-only.
902913 
914 - `type: "text"`
915 
903916 - `text: string`
904917 
905918 The text content.
906919 
907920 minLength: 1
908 
909 - `type: "text"`
910 
911 - `type: "system.message"`
912921 
913922 - `processed_at: optional string or null`
914923