--- title: "Changes to Send Events" method: POST path: "/v1/sessions/{session_id}/events?beta=true" --- # Changes to Send Events `POST /v1/sessions/{session_id}/events?beta=true` > Every recorded change to this operation, newest first. ## Timeline Changed in 21 of 287 revisions. - **2026-11-05** `037a593978dc`: 1 info - **2026-10-23** `f538a797852c`: 1 info - **2026-10-23** `8071e43a8476`: 1 info - **2026-10-22** `376dea998624`: 1 info - **2026-10-21** `94c83daca660`: 96 breaking, 96 info - **2026-10-21** `b6f3fef9c0b5`: 1 info - **2026-10-14** `e6a88013f0b2`: 1 info - **2026-09-30** `d721a6487a16`: 1 info - **2026-09-30** `ab91b3e513b5`: 1 info - **2026-09-22** `257523f5aeb5`: 2 info - **2026-09-18** `3144b1e8c9e4`: 1 breaking, 1 warning - **2026-09-04** `4789294140a2`: 1 info - **2026-08-19** `d2b230555b7f`: 26 breaking, 23 info - **2026-08-07** `93d8fd7d6493`: 1 breaking, 3 info - **2026-06-09** `2336fecb081b`: 1 breaking, 3 info - **2026-05-19** `40e330aba8bc`: 1 breaking, 3 info - **2026-05-13** `88ef81f4f457`: 1 breaking, 1 warning - **2026-05-13** `80953dd6bb30`: 1 breaking, 3 info - **2026-05-06** `a4186730f56c`: 1 breaking, 7 info - **2026-04-09** `d87d3ef6f636`: 20 breaking - **2026-04-08** `69486316563e`: 1 info ## Changes - **2026-11-05** `037a593978dc`: 1 info - added the enum value `admin-user-sign-out-2026-10-08` to the property `items/anyOf[subschema #2]/` of the `header` request parameter `anthropic-beta` - **2026-10-23** `f538a797852c`: 1 info - added the enum value `experimental-claude-tag-2026-10-21` to the property `items/anyOf[subschema #2]/` of the `header` request parameter `anthropic-beta` - **2026-10-23** `8071e43a8476`: 1 info - added the enum value `analytics-usage-cost-2026-08-24` to the property `items/anyOf[subschema #2]/` of the `header` request parameter `anthropic-beta` - **2026-10-22** `376dea998624`: 1 info - added the enum value `message-threads-2026-08-12` to the property `items/anyOf[subschema #2]/` of the `header` request parameter `anthropic-beta` - **2026-10-21** `94c83daca660`: 96 breaking, 96 info - the `media_type` request property const value `text/plain` was added - the `media_type` request property const value `text/plain` was added - the `media_type` request property const value `text/plain` was added - the `type` request property const value `base64` was added - the `type` request property const value `base64` was added - the `type` request property const value `base64` was added - the `type` request property const value `base64` was added - the `type` request property const value `base64` was added - the `type` request property const value `base64` was added - the `type` request property const value `document` was added - the `type` request property const value `document` was added - the `type` request property const value `document` was added - the `type` request property const value `file` was added - the `type` request property const value `file` was added - the `type` request property const value `file` was added - the `type` request property const value `file` was added - the `type` request property const value `file` was added - the `type` request property const value `file` was added - the `type` request property const value `file` was added - the `type` request property const value `image` was added - the `type` request property const value `image` was added - the `type` request property const value `image` was added - the `type` request property const value `redacted` was added - the `type` request property const value `search_result` was added - the `type` request property const value `search_result` was added - the `type` request property const value `system.message` was added - the `type` request property const value `text` was added - the `type` request property const value `text` was added - the `type` request property const value `text` was added - the `type` request property const value `text` was added - the `type` request property const value `text` was added - the `type` request property const value `text` was added - the `type` request property const value `text` was added - the `type` request property const value `text` was added - the `type` request property const value `text` was added - the `type` request property const value `text` was added - the `type` request property const value `url` was added - the `type` request property const value `url` was added - the `type` request property const value `url` was added - the `type` request property const value `url` was added - …152 more - **2026-10-21** `b6f3fef9c0b5`: 1 info - added the enum value `webhooks-2026-10-07` to the property `items/anyOf[subschema #2]/` of the `header` request parameter `anthropic-beta` - **2026-10-14** `e6a88013f0b2`: 1 info - added the enum value `telemetry-destinations-2026-08-11` to the property `items/anyOf[subschema #2]/` of the `header` request parameter `anthropic-beta` - **2026-09-30** `d721a6487a16`: 1 info - added the enum value `spend-limit-reads-2026-09-26` to the property `items/anyOf[subschema #2]/` of the `header` request parameter `anthropic-beta` - **2026-09-30** `ab91b3e513b5`: 1 info - added the enum value `ce-plugins-2026-09-01` to the property `items/anyOf[subschema #2]/` of the `header` request parameter `anthropic-beta` - **2026-09-22** `257523f5aeb5`: 2 info - added the enum value `inline-tools-2026-09-15` to the property `items/anyOf[subschema #2]/` of the `header` request parameter `anthropic-beta` - added the enum value `mcp-client-2026-09-15` to the property `items/anyOf[subschema #2]/` of the `header` request parameter `anthropic-beta` - **2026-09-18** `3144b1e8c9e4`: 1 breaking, 1 warning - for the `header` request parameter `anthropic-beta`, the type changed from `string` to `array` - for the `header` request parameter `anthropic-beta`, the type of property `items/` changed from `string` to no type - **2026-09-04** `4789294140a2`: 1 info - added the new optional `header` request parameter `anthropic-workspace-id` - **2026-08-19** `d2b230555b7f`: 26 breaking, 23 info - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/context` became not nullable - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/title` became not nullable - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/is_error` became not nullable - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserDefineOutcomeEventParams]/max_iterations` became not nullable - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserInterruptEventParams]/session_thread_id` became not nullable - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/context` became not nullable - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/title` became not nullable - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolConfirmationEventParams]/deny_message` became not nullable - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/context` became not nullable - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/title` became not nullable - the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolResultEventParams]/is_error` became not nullable - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEvent]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/context` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEvent]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/title` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEvent]/is_error` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEvent]/session_thread_id` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserDefineOutcomeEvent]/max_iterations` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserInterruptEvent]/session_thread_id` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEvent]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/context` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEvent]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/title` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolConfirmationEvent]/deny_message` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolConfirmationEvent]/session_thread_id` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolResultEvent]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/context` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolResultEvent]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/title` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolResultEvent]/is_error` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - response property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolResultEvent]/session_thread_id` list-of-types was widened by adding types `null` to media type `application/json` of response `200` - the `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolConfirmationEvent]/deny_message` response property's maxLength was unset from `10000` for the response status `200` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/context` list-of-types was widened by adding types `null` to media type `application/json` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/title` list-of-types was widened by adding types `null` to media type `application/json` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/is_error` list-of-types was widened by adding types `null` to media type `application/json` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserDefineOutcomeEventParams]/max_iterations` list-of-types was widened by adding types `null` to media type `application/json` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserInterruptEventParams]/session_thread_id` list-of-types was widened by adding types `null` to media type `application/json` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/context` list-of-types was widened by adding types `null` to media type `application/json` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/title` list-of-types was widened by adding types `null` to media type `application/json` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolConfirmationEventParams]/deny_message` list-of-types was widened by adding types `null` to media type `application/json` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/context` list-of-types was widened by adding types `null` to media type `application/json` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/title` list-of-types was widened by adding types `null` to media type `application/json` - request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolResultEventParams]/is_error` list-of-types was widened by adding types `null` to media type `application/json` - removed `#/components/schemas/BetaTimestamp` from the `data/items/oneOf[#/components/schemas/BetaManagedAgentsSystemMessageEvent]/processed_at` response property `allOf` list for the response status `200` - removed `#/components/schemas/BetaTimestamp` from the `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEvent]/processed_at` response property `allOf` list for the response status `200` - removed `#/components/schemas/BetaTimestamp` from the `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserInterruptEvent]/processed_at` response property `allOf` list for the response status `200` - …9 more - **2026-08-07** `93d8fd7d6493`: 1 breaking, 3 info - added `#/components/schemas/BetaManagedAgentsRedactedBlock` to the `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEvent]/content/items/` response property `oneOf` list for the response status `200` - added `redacted` discriminator mapping keys to the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/` request property - added `#/components/schemas/BetaManagedAgentsRedactedBlock` to the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/` request property `oneOf` list - added `redacted` discriminator mapping keys to the `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEvent]/content/items/` response property for the response status `200` - **2026-06-09** `2336fecb081b`: 1 breaking, 3 info - added `#/components/schemas/BetaManagedAgentsSystemMessageEvent` to the `data/items/` response property `oneOf` list for the response status `200` - added `system.message` discriminator mapping keys to the `events/items/` request property - added `#/components/schemas/BetaManagedAgentsSystemMessageEventParams` to the `events/items/` request property `oneOf` list - added `system.message` discriminator mapping keys to the `data/items/` response property for the response status `200` - **2026-05-19** `40e330aba8bc`: 1 breaking, 3 info - added `#/components/schemas/BetaManagedAgentsUserToolResultEvent` to the `data/items/` response property `oneOf` list for the response status `200` - added `user.tool_result` discriminator mapping keys to the `events/items/` request property - added `#/components/schemas/BetaManagedAgentsUserToolResultEventParams` to the `events/items/` request property `oneOf` list - added `user.tool_result` discriminator mapping keys to the `data/items/` response property for the response status `200` - **2026-05-13** `88ef81f4f457`: 1 breaking, 1 warning - removed the required property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEvent]/content/items/oneOf[#/components/schemas/BetaManagedAgentsSearchResultBlock]/tool_use_id` from the response with the `200` status - removed the request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsSearchResultBlock]/tool_use_id` - **2026-05-13** `80953dd6bb30`: 1 breaking, 3 info - added `#/components/schemas/BetaManagedAgentsSearchResultBlock` to the `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEvent]/content/items/` response property `oneOf` list for the response status `200` - added `search_result` discriminator mapping keys to the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/` request property - added `#/components/schemas/BetaManagedAgentsSearchResultBlock` to the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/` request property `oneOf` list - added `search_result` discriminator mapping keys to the `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEvent]/content/items/` response property for the response status `200` - **2026-05-06** `a4186730f56c`: 1 breaking, 7 info - added `#/components/schemas/BetaManagedAgentsUserDefineOutcomeEvent` to the `data/items/` response property `oneOf` list for the response status `200` - added the new optional request property `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserInterruptEventParams]/session_thread_id` - added `user.define_outcome` discriminator mapping keys to the `events/items/` request property - added `#/components/schemas/BetaManagedAgentsUserDefineOutcomeEventParams` to the `events/items/` request property `oneOf` list - added the optional property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEvent]/session_thread_id` to the response with the `200` status - added the optional property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserInterruptEvent]/session_thread_id` to the response with the `200` status - added the optional property `data/items/oneOf[#/components/schemas/BetaManagedAgentsUserToolConfirmationEvent]/session_thread_id` to the response with the `200` status - added `user.define_outcome` discriminator mapping keys to the `data/items/` response property for the response status `200` - **2026-04-09** `d87d3ef6f636`: 20 breaking - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/source/allOf[#/components/schemas/BetaManagedAgentsDocumentSource]/oneOf[#/components/schemas/BetaManagedAgentsBase64DocumentSource]/data` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/source/allOf[#/components/schemas/BetaManagedAgentsDocumentSource]/oneOf[#/components/schemas/BetaManagedAgentsBase64DocumentSource]/media_type` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/source/allOf[#/components/schemas/BetaManagedAgentsDocumentSource]/oneOf[#/components/schemas/BetaManagedAgentsFileDocumentSource]/file_id` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/source/allOf[#/components/schemas/BetaManagedAgentsDocumentSource]/oneOf[#/components/schemas/BetaManagedAgentsPlainTextDocumentSource]/data` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/source/allOf[#/components/schemas/BetaManagedAgentsDocumentSource]/oneOf[#/components/schemas/BetaManagedAgentsURLDocumentSource]/url` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsImageBlock]/source/allOf[#/components/schemas/BetaManagedAgentsImageSource]/oneOf[#/components/schemas/BetaManagedAgentsBase64ImageSource]/data` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsImageBlock]/source/allOf[#/components/schemas/BetaManagedAgentsImageSource]/oneOf[#/components/schemas/BetaManagedAgentsBase64ImageSource]/media_type` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsImageBlock]/source/allOf[#/components/schemas/BetaManagedAgentsImageSource]/oneOf[#/components/schemas/BetaManagedAgentsFileImageSource]/file_id` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsImageBlock]/source/allOf[#/components/schemas/BetaManagedAgentsImageSource]/oneOf[#/components/schemas/BetaManagedAgentsURLImageSource]/url` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserCustomToolResultEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsTextBlock]/text` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/source/allOf[#/components/schemas/BetaManagedAgentsDocumentSource]/oneOf[#/components/schemas/BetaManagedAgentsBase64DocumentSource]/data` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/source/allOf[#/components/schemas/BetaManagedAgentsDocumentSource]/oneOf[#/components/schemas/BetaManagedAgentsBase64DocumentSource]/media_type` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/source/allOf[#/components/schemas/BetaManagedAgentsDocumentSource]/oneOf[#/components/schemas/BetaManagedAgentsFileDocumentSource]/file_id` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/source/allOf[#/components/schemas/BetaManagedAgentsDocumentSource]/oneOf[#/components/schemas/BetaManagedAgentsPlainTextDocumentSource]/data` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsDocumentBlock]/source/allOf[#/components/schemas/BetaManagedAgentsDocumentSource]/oneOf[#/components/schemas/BetaManagedAgentsURLDocumentSource]/url` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsImageBlock]/source/allOf[#/components/schemas/BetaManagedAgentsImageSource]/oneOf[#/components/schemas/BetaManagedAgentsBase64ImageSource]/data` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsImageBlock]/source/allOf[#/components/schemas/BetaManagedAgentsImageSource]/oneOf[#/components/schemas/BetaManagedAgentsBase64ImageSource]/media_type` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsImageBlock]/source/allOf[#/components/schemas/BetaManagedAgentsImageSource]/oneOf[#/components/schemas/BetaManagedAgentsFileImageSource]/file_id` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsImageBlock]/source/allOf[#/components/schemas/BetaManagedAgentsImageSource]/oneOf[#/components/schemas/BetaManagedAgentsURLImageSource]/url` request property's minLength was increased from `0` to `1` - the `events/items/oneOf[#/components/schemas/BetaManagedAgentsUserMessageEventParams]/content/items/oneOf[#/components/schemas/BetaManagedAgentsTextBlock]/text` request property's minLength was increased from `0` to `1` - **2026-04-08** `69486316563e`: 1 info - endpoint added --- [Operation](https://skmtc.dev/anthropics/apis/anthropic-api/docs/v1/sessions/:session_id/events%3Fbeta=true/post.md) - [API](https://skmtc.dev/anthropics/apis/anthropic-api.md) - [Page](https://skmtc.dev/anthropics/apis/anthropic-api/changes/v1/sessions/:session_id/events%3Fbeta=true/post)