--- title: "Compact Agent Session" method: POST path: "/v1/agent_sessions/{session_id}/compact" tags: ["chat"] --- # Compact Agent Session `POST /v1/agent_sessions/{session_id}/compact` ## Path parameters - `session_id` string, required ## Request body - CompactAgentSessionRequestBody — Request a model-generated checkpoint for a persisted conversation. - `model` union, required - CustomProviderModelSelection — Chat against a stored custom provider record. - `providerType` 'custom', required - `providerId` string, required - `modelName` string, required - BuiltInProviderModelSelection — Chat against a Phoenix built-in provider. Credentials and connection details (base URL, Azure endpoint, AWS region) are resolved from the secret store first and the process environment second. - `providerType` 'builtin', required - `provider` 'OPENAI' | 'AZURE_OPENAI' | 'ANTHROPIC' | 'GOOGLE' | 'DEEPSEEK' | 'XAI' | 'OLLAMA' | 'AWS' | 'CEREBRAS' | 'FIREWORKS' | 'GROQ' | 'MOONSHOT' | 'PERPLEXITY' | 'TOGETHER', required - `modelName` string, required ## Response `200` Successful Response - CompactAgentSessionResponseBody — The checkpoint message this request created. A 200 always means a new checkpoint was persisted; every other outcome is an HTTP 409 whose body's ``code`` says why (see ``AgentSessionConflictError``). - `data` PhoenixUIMessage, required — ``UIMessage`` with metadata narrowed to the Phoenix wire shapes. - `id` string, required - `role` 'system' | 'user' | 'assistant', required - `metadata` MessageMetadata — ``UIMessage.metadata`` as a registry of namespaces. - `phoenix` union - PhoenixAssistantMessageMetadata — The ``phoenix`` metadata namespace of an assistant message. - `type` 'assistant', required - `sessionId` string, required - `turnTraceContext` TurnTraceContext — The trace identity a turn's spans are parented to. - `traceId` string, required - `rootSpanId` string, required - `startedAt` string, date-time, required - `usage` AssistantMessageMetadataUsage - `tokens` AssistantMessageMetadataUsageTokens, required - … - `promptDetails` AssistantMessageMetadataUsageCacheTokenDetails — Prompt-cache token counts, mounted as the usage payload's ``prompt_details`` because cached tokens are a breakdown of the prompt. - … - `interrupted` boolean - PhoenixUserMessageMetadata — The ``phoenix`` metadata namespace the browser attaches to outgoing user messages. - `type` 'user', required - `currentDateTime` string, required - `timeZone` string, required - `isCompactionMessage` boolean - `pydantic_ai` PydanticAIMessageMetadata — Local pin of pydantic-ai's message-level ``pydantic_ai`` metadata namespace (its private ``_PydanticAIMessageMetadata``), merged into the assistant metadata by the stream's metadata chunk. - `timestamp` string, date-time, nullable - `parts` union[], required - union - TextUIPart — A text part of a message. - `type` 'text' - `text` string, required - `state` 'streaming' | 'done', nullable - `providerMetadata` object, nullable - ReasoningUIPart — A reasoning part of a message. - `type` 'reasoning' - `text` string, required - `state` 'streaming' | 'done', nullable - `providerMetadata` object, nullable - ToolInputStreamingPart — Tool part in input-streaming state. - `type` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'input-streaming' - `input` unknown - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - ToolInputAvailablePart — Tool part in input-available state. - `type` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'input-available' - `input` unknown - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - PhoenixDbTypesDataStreamProtocolRequestTypesToolOutputAvailablePart — Tool part in output-available state. - `type` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'output-available' - `input` unknown - `output` unknown - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `resultProviderMetadata` object, nullable - `preliminary` boolean, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - PhoenixDbTypesDataStreamProtocolRequestTypesToolOutputErrorPart — Tool part in output-error state. - `type` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'output-error' - `input` unknown - `rawInput` unknown - `errorText` string, required - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `resultProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - ToolApprovalRequestedPart — Tool part in approval-requested state (awaiting user decision). - `type` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'approval-requested' - `input` unknown - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - ToolApprovalRespondedPart — Tool part in approval-responded state (user approved/denied, execution pending). - `type` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'approval-responded' - `input` unknown - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - ToolOutputDeniedPart — Tool part in output-denied state (tool was denied, terminal state). - `type` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'output-denied' - `input` unknown - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - DynamicToolInputStreamingPart — Dynamic tool part in input-streaming state. - `type` 'dynamic-tool' - `toolName` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'input-streaming' - `input` unknown - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - DynamicToolInputAvailablePart — Dynamic tool part in input-available state. - `type` 'dynamic-tool' - `toolName` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'input-available' - `input` unknown, required - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - PhoenixDbTypesDataStreamProtocolRequestTypesDynamicToolOutputAvailablePart — Dynamic tool part in output-available state. - `type` 'dynamic-tool' - `toolName` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'output-available' - `input` unknown, required - `output` unknown, required - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `resultProviderMetadata` object, nullable - `preliminary` boolean, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - PhoenixDbTypesDataStreamProtocolRequestTypesDynamicToolOutputErrorPart — Dynamic tool part in output-error state. - `type` 'dynamic-tool' - `toolName` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'output-error' - `input` unknown, required - `errorText` string, required - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `resultProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - DynamicToolApprovalRequestedPart — Dynamic tool part in approval-requested state (awaiting user decision). - `type` 'dynamic-tool' - `toolName` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'approval-requested' - `input` unknown, required - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - DynamicToolApprovalRespondedPart — Dynamic tool part in approval-responded state (user approved/denied, execution pending). - `type` 'dynamic-tool' - `toolName` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'approval-responded' - `input` unknown, required - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - DynamicToolOutputDeniedPart — Dynamic tool part in output-denied state (tool was denied, terminal state). - `type` 'dynamic-tool' - `toolName` string, required - `toolCallId` string, required - `title` string, nullable - `state` 'output-denied' - `input` unknown, required - `providerExecuted` boolean, nullable - `callProviderMetadata` object, nullable - `approval` union - ToolApprovalRequested — Tool approval in requested state (awaiting user response). - … - ToolApprovalResponded — Tool approval in responded state (user has approved or denied). - … - SourceUrlUIPart — A source part of a message. - `type` 'source-url' - `sourceId` string, required - `url` string, required - `title` string, nullable - `providerMetadata` object, nullable - SourceDocumentUIPart — A document source part of a message. - `type` 'source-document' - `sourceId` string, required - `mediaType` string, required - `title` string, required - `filename` string, nullable - `providerMetadata` object, nullable - FileUIPart — A file part of a message. - `type` 'file' - `mediaType` string, required - `filename` string, nullable - `url` string, required - `providerMetadata` object, nullable - DataUIPart — Data part with dynamic type based on data name. - `type` string, required - `id` string, nullable - `data` unknown, required - StepStartUIPart — A step boundary part of a message. - `type` 'step-start' ## Other responses - `400` — Bad Request - `401` — Unauthorized - `403` — Forbidden - `404` — Not Found - `409` — The request conflicts with the session's current state; the body's ``code`` field says how. - `422` — Validation Error - `502` — Bad Gateway - `507` — Insufficient Storage --- [API](https://skmtc.net/arize-ai/apis/arize-phoenix-rest-api.md) · [All operations](https://skmtc.net/arize-ai/apis/arize-phoenix-rest-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/arize-ai/arize-phoenix-rest-api/revisions/8ac3f55fbe00/schema)