Changes to Count tokens in a Message

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #3: SystemInputMessage]/content/anyOf[subschema #2: Blocks]/items/oneOf[subschema #2: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the model request property anyOf list

removed subschema #1 subschema #2 from the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #3: SystemInputMessage]/content/anyOf[subschema #2: Blocks]/items/oneOf[subschema #2: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the model request property anyOf list

added subschema #1 subschema #2 to the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

removed subschema #1 subschema #2 from the messages/items/oneOf[subschema #3: SystemInputMessage]/content/anyOf[subschema #2: Blocks]/items/oneOf[subschema #2: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #1 subschema #2 from the model request property anyOf list

removed subschema #1 subschema #2 from the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #3: SystemInputMessage]/content/anyOf[subschema #2: Blocks]/items/oneOf[subschema #2: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the model request property anyOf list

added subschema #1 subschema #2 to the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #1: UserInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #2: AssistantInputMessage]/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #1 subschema #2 to the messages/items/oneOf[subschema #3: SystemInputMessage]/content/anyOf[subschema #2: Blocks]/items/oneOf[subschema #2: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #2 to the model request property anyOf list

added subschema #1 subschema #2 to the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

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

added the enum value experimental-claude-tag-2026-10-21 to the property items/anyOf[subschema #2]/ of the header request parameter anthropic-beta

added the enum value analytics-usage-cost-2026-08-24 to the property items/anyOf[subschema #2]/ of the header request parameter anthropic-beta

added the enum value message-threads-2026-08-12 to the property items/anyOf[subschema #2]/ of the header request parameter anthropic-beta

the messages/items request property type changed from object to no type

removed the request property messages/items/clear_at

removed the request property messages/items/content

removed the request property messages/items/output_config

removed the request property messages/items/role

added assistant system user discriminator mapping keys to the messages/items request property

added BetaUserInputMessage BetaAssistantInputMessage BetaSystemInputMessage to the messages/items request property oneOf list

added the enum value webhooks-2026-10-07 to the property items/anyOf[subschema #2]/ of the header request parameter anthropic-beta

added the enum value telemetry-destinations-2026-08-11 to the property items/anyOf[subschema #2]/ of the header request parameter anthropic-beta

removed subschema #15 subschema #16 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #15 subschema #16 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #15 subschema #16 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

removed subschema #15 subschema #16 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

removed subschema #15 subschema #16 from the model request property anyOf list

removed subschema #15 subschema #16 from the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #15 subschema #16 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #15 subschema #16 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #15 subschema #16 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #15 subschema #16 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #15 subschema #16 to the model request property anyOf list

added subschema #15 subschema #16 to the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

the error response's property type changed from no type to object for status 400

the error response's property type changed from no type to object for status 413

the error response's property type changed from no type to object for status 429

the error response's property type changed from no type to object for status 529

added the optional property error/details to the response with the 400 status

added the optional property error/details to the response with the 413 status

added the optional property error/details to the response with the 429 status

added the optional property error/details to the response with the 529 status

removed discriminator from error response property for the response status 400

removed discriminator from error response property for the response status 413

removed discriminator from error response property for the response status 429

removed discriminator from error response property for the response status 529

removed BetaInvalidRequestError BetaAuthenticationError BetaBillingError BetaPermissionError BetaNotFoundError BetaRateLimitError BetaGatewayTimeoutError BetaAPIError BetaOverloadedError from the error response property oneOf list for the response status 400

removed BetaInvalidRequestError BetaAuthenticationError BetaBillingError BetaPermissionError BetaNotFoundError BetaRateLimitError BetaGatewayTimeoutError BetaAPIError BetaOverloadedError from the error response property oneOf list for the response status 413

removed BetaInvalidRequestError BetaAuthenticationError BetaBillingError BetaPermissionError BetaNotFoundError BetaRateLimitError BetaGatewayTimeoutError BetaAPIError BetaOverloadedError from the error response property oneOf list for the response status 429

removed BetaInvalidRequestError BetaAuthenticationError BetaBillingError BetaPermissionError BetaNotFoundError BetaRateLimitError BetaGatewayTimeoutError BetaAPIError BetaOverloadedError from the error response property oneOf list for the response status 529

added the required property error/message to the response with the 400 status

added the required property error/message to the response with the 413 status

added the required property error/message to the response with the 429 status

added the required property error/message to the response with the 529 status

added the required property error/type to the response with the 400 status

added the required property error/type to the response with the 413 status

added the required property error/type to the response with the 429 status

added the required property error/type to the response with the 529 status

added subschema #1 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #1 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #1 to the model request property anyOf list

added subschema #1 to the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #18 subschema #19 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #18 subschema #19 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #18 subschema #19 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

removed subschema #18 subschema #19 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

removed subschema #18 subschema #19 from the model request property anyOf list

removed subschema #18 subschema #19 from the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added the enum value spend-limit-reads-2026-09-26 to the property items/anyOf[subschema #2]/ of the header request parameter anthropic-beta

added subschema #18 subschema #19 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #18 subschema #19 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #18 subschema #19 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #18 subschema #19 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #18 subschema #19 to the model request property anyOf list

added subschema #18 subschema #19 to the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added the enum value ce-plugins-2026-09-01 to the property items/anyOf[subschema #2]/ of the header request parameter anthropic-beta

removed subschema #4 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #4 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

removed subschema #4 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

removed subschema #4 from the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

removed subschema #4 from the model request property anyOf list

removed subschema #4 from the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #5 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes/anyOf[subschema #1]/items/oneOf[subschema #1: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #5 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool/oneOf[subschema #4: ToolChangeToolDefinition]/definition/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added subschema #1 subschema #5 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #1 subschema #5 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #1 subschema #5 to the model request property anyOf list

added subschema #1 subschema #5 to the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added between_tools discriminator mapping keys to the thinking request property

added BetaThinkingConfigBetweenTools to the thinking request property oneOf list

removed discriminator from context_management/anyOf[subschema #1: ContextManagementConfig]/edits/items/oneOf[subschema #2: ClearThinking20251015]/keep/anyOf[subschema #1] request property

added the new optional request property messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/tool_changes

added the new optional request property tools/items/oneOf[subschema #28: MCPToolset]/tools

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

added subschema #3 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #23: RequestFallbackBlock -> subschema #24: RequestFallbackBlock]/from/model request property anyOf list

added subschema #3 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #23: RequestFallbackBlock -> subschema #24: RequestFallbackBlock]/to/model request property anyOf list

added subschema #3 to the model request property anyOf list

added subschema #3 to the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added mcp_tool_listing discriminator mapping keys to the messages/items/content/anyOf[subschema #2]/items request property

added tool_definition discriminator mapping keys to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool request property

added BetaRequestMCPToolListingBlock to the messages/items/content/anyOf[subschema #2]/items request property oneOf list

added BetaToolChangeToolDefinition to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestToolAdditionBlock]/tool request property oneOf list

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

added the new optional request property compaction

added the new optional request property messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #20: RequestCompactionBlock]/signature

added the new optional request property tools/items/oneOf[subschema #19: WebFetchTool_20250910]/url_sources

added the new optional request property tools/items/oneOf[subschema #21: WebFetchTool_20260209]/url_sources

added the new optional request property tools/items/oneOf[subschema #22: WebFetchTool_20260309]/url_sources

added the new optional request property tools/items/oneOf[subschema #24: WebFetchTool_20260318]/url_sources

added the new content_too_large enum value to the request property messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #11: RequestWebFetchToolResultBlock]/content/anyOf[subschema #1: RequestWebFetchToolResultError]/error_code

added the new optional header request parameter anthropic-workspace-id

added the non-success response with the status 400

added the non-success response with the status 401

added the non-success response with the status 403

added the non-success response with the status 404

added the non-success response with the status 408

added the non-success response with the status 409

added the non-success response with the status 412

added the non-success response with the status 413

added the non-success response with the status 429

added the non-success response with the status 431

added the non-success response with the status 499

added the non-success response with the status 500

added the non-success response with the status 501

added the non-success response with the status 503

added the non-success response with the status 504

added the non-success response with the status 529

removed the request property tools/items/oneOf[subschema #14: ComputerToolset_20260801]/allowed_callers

removed the request property tools/items/oneOf[subschema #8: BrowserToolset_20260801]/allowed_callers

added the new optional request property messages/items/clear_at

added the new optional request property messages/items/output_config

added the new optional request property thinking/oneOf[subschema #1: ThinkingConfigEnabled]/block_binding

added the new optional request property thinking/oneOf[subschema #3: ThinkingConfigAdaptive]/block_binding

added subschema #2 subschema #3 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #23: RequestFallbackBlock]/from/model request property anyOf list

added subschema #2 subschema #3 to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #23: RequestFallbackBlock]/to/model request property anyOf list

added subschema #2 subschema #3 to the model request property anyOf list

added subschema #2 subschema #3 to the tools/items/oneOf[subschema #25: AdvisorTool_20260301]/model request property anyOf list

added the new updates enum value to the request property thinking/oneOf[subschema #1: ThinkingConfigEnabled]/display/anyOf[subschema #1: ThinkingDisplayMode]

added the new updates enum value to the request property thinking/oneOf[subschema #3: ThinkingConfigAdaptive]/display/anyOf[subschema #1: ThinkingDisplayMode]

added the new optional request property messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #11: RequestWebFetchToolResultBlock]/content/anyOf[subschema #2: RequestWebFetchResultBlock]/content/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #2: RequestImageBlock]/transformations

added the new optional request property messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #2: RequestImageBlock]/transformations

added the new optional request property messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #3: RequestDocumentBlock]/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #2: RequestImageBlock]/transformations

added the new optional request property messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #7: RequestToolUseBlock]/toolset_name

added the new optional request property messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #2: RequestImageBlock]/transformations

added the new optional request property messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #4: RequestDocumentBlock]/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #2: RequestImageBlock]/transformations

added the new optional request property messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/toolset_name

added browser_state discriminator mapping keys to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items request property

added BetaBrowserToolset_20260801 BetaComputerToolset_20260801 to the tools/items request property oneOf list

added BetaRequestBrowserStateBlock to the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items request property oneOf list

removed BetaRequestMidConvSystemBlock from the messages/items/content/anyOf[subschema #2]/items request property oneOf list

removed mid_conv_system discriminator mapping keys from the messages/items/content/anyOf[subschema #2]/items request property

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #11: RequestWebFetchToolResultBlock]/content/anyOf[subschema #2: RequestWebFetchResultBlock]/content/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #1: RequestCharLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #11: RequestWebFetchToolResultBlock]/content/anyOf[subschema #2: RequestWebFetchResultBlock]/content/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #2: RequestPageLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #11: RequestWebFetchToolResultBlock]/content/anyOf[subschema #2: RequestWebFetchResultBlock]/content/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #3: RequestContentBlockLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #18: RequestMCPToolResultBlock]/content/anyOf[subschema #2: beta_mcp_tool_result_block_param_content]/items/citations/anyOf[subschema #1]/items/oneOf[subschema #1: RequestCharLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #18: RequestMCPToolResultBlock]/content/anyOf[subschema #2: beta_mcp_tool_result_block_param_content]/items/citations/anyOf[subschema #1]/items/oneOf[subschema #2: RequestPageLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #18: RequestMCPToolResultBlock]/content/anyOf[subschema #2: beta_mcp_tool_result_block_param_content]/items/citations/anyOf[subschema #1]/items/oneOf[subschema #3: RequestContentBlockLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #1: RequestCharLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #2: RequestPageLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #3: RequestContentBlockLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestMidConvSystemBlock]/content/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #1: RequestCharLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestMidConvSystemBlock]/content/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #2: RequestPageLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #21: RequestMidConvSystemBlock]/content/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #3: RequestContentBlockLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #3: RequestDocumentBlock]/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #1: RequestCharLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #3: RequestDocumentBlock]/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #2: RequestPageLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #3: RequestDocumentBlock]/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #3: RequestContentBlockLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #4: RequestSearchResultBlock]/content/items/citations/anyOf[subschema #1]/items/oneOf[subschema #1: RequestCharLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #4: RequestSearchResultBlock]/content/items/citations/anyOf[subschema #1]/items/oneOf[subschema #2: RequestPageLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #4: RequestSearchResultBlock]/content/items/citations/anyOf[subschema #1]/items/oneOf[subschema #3: RequestContentBlockLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #1: RequestCharLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #2: RequestPageLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #3: RequestContentBlockLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #3: RequestSearchResultBlock]/content/items/citations/anyOf[subschema #1]/items/oneOf[subschema #1: RequestCharLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #3: RequestSearchResultBlock]/content/items/citations/anyOf[subschema #1]/items/oneOf[subschema #2: RequestPageLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #3: RequestSearchResultBlock]/content/items/citations/anyOf[subschema #1]/items/oneOf[subschema #3: RequestContentBlockLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #4: RequestDocumentBlock]/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #1: RequestCharLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #4: RequestDocumentBlock]/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #2: RequestPageLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the messages/items/content/anyOf[subschema #2]/items/oneOf[subschema #8: RequestToolResultBlock]/content/anyOf[subschema #2]/items/oneOf[subschema #4: RequestDocumentBlock]/source/oneOf[subschema #3: ContentBlockSource]/content/anyOf[subschema #2: beta_content_block_source_content]/items/oneOf[subschema #1: RequestTextBlock]/citations/anyOf[subschema #1]/items/oneOf[subschema #3: RequestContentBlockLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the system/anyOf[subschema #2]/items/citations/anyOf[subschema #1]/items/oneOf[subschema #1: RequestCharLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the system/anyOf[subschema #2]/items/citations/anyOf[subschema #1]/items/oneOf[subschema #2: RequestPageLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500

the system/anyOf[subschema #2]/items/citations/anyOf[subschema #1]/items/oneOf[subschema #3: RequestContentBlockLocationCitation]/document_title/anyOf[subschema #1] request property's maxLength was increased from 255 to 500