Langflow
Langflow Chat API

The Chat API from Langflow — 6 operation(s) for chat.
Documentation GitHub OpenAPI
OpenAPI Specification

openapi: 3.1.0
info:
  title: Langflow Base Chat API
  version: 1.9.0
tags:
- name: Chat
paths:
  /api/v1/build/{flow_id}/flow:
    post:
      description: 'Build and process a flow, returning a job ID for event polling.<br><br>This endpoint requires authentication through the CurrentActiveUser dependency.<br>For public flows that don''t require authentication, use the /build_public_tmp/flow_id/flow endpoint.<br><br>Args:<br>    flow_id: UUID of the flow to build<br>    background_tasks: Background tasks manager<br>    inputs: Optional input values for the flow<br>    data: Optional flow data<br>    files: Optional files to include<br>    stop_component_id: Optional ID of component to stop at<br>    start_component_id: Optional ID of component to start from<br>    log_builds: Whether to log the build process<br>    current_user: The authenticated user<br>    queue_service: Queue service for job management<br>    flow_name: Optional name for the flow<br>    event_delivery: Optional event delivery type - default is streaming<br><br>Returns:<br>    Dict with job_id that can be used to poll for build status'
      operationId: build_flow_api_v1_build__flow_id__flow_post
      parameters:
      - in: path
        name: flow_id
        required: true
        schema:
          format: uuid
          title: Flow Id
          type: string
      - in: query
        name: stop_component_id
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          title: Stop Component Id
      - in: query
        name: start_component_id
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          title: Start Component Id
      - in: query
        name: log_builds
        required: false
        schema:
          default: true
          title: Log Builds
          type: boolean
      - in: query
        name: flow_name
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          title: Flow Name
      - in: query
        name: event_delivery
        required: false
        schema:
          $ref: '#/components/schemas/EventDeliveryType'
          default: polling
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/Body_build_flow_api_v1_build__flow_id__flow_post'
      responses:
        '200':
          content:
            application/json:
              schema: {}
          description: Successful Response
        '422':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
          description: Validation Error
      security:
      - OAuth2PasswordBearerCookie: []
      - API key query: []
      - API key header: []
      summary: Build Flow
      tags:
      - Chat
  /api/v1/build/{job_id}/cancel:
    post:
      description: Cancel a specific build job.<br><br>Requires authentication and ownership verification to prevent a user from<br>aborting another user's running build (DoS via job cancellation).<br>Jobs with no registered owner (build_public_tmp) are accessible to any<br>authenticated user, consistent with get_build_events.
      operationId: cancel_build_api_v1_build__job_id__cancel_post
      parameters:
      - in: path
        name: job_id
        required: true
        schema:
          title: Job Id
          type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CancelFlowResponse'
          description: Successful Response
        '422':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
          description: Validation Error
      security:
      - OAuth2PasswordBearerCookie: []
      - API key query: []
      - API key header: []
      summary: Cancel Build
      tags:
      - Chat
  /api/v1/build/{job_id}/events:
    get:
      description: Get events for a specific build job.<br><br>Requires authentication and ownership verification. A job owner is registered<br>when build_flow is called; if a registered owner does not match the requesting<br>user the endpoint returns 404 to avoid leaking job existence.<br>Jobs started via build_public_tmp have no registered owner and remain accessible<br>to any authenticated user.
      operationId: get_build_events_api_v1_build__job_id__events_get
      parameters:
      - in: path
        name: job_id
        required: true
        schema:
          title: Job Id
          type: string
      - in: query
        name: event_delivery
        required: false
        schema:
          $ref: '#/components/schemas/EventDeliveryType'
          default: streaming
      responses:
        '200':
          content:
            application/json:
              schema: {}
          description: Successful Response
        '422':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
          description: Validation Error
      security:
      - OAuth2PasswordBearerCookie: []
      - API key query: []
      - API key header: []
      summary: Get Build Events
      tags:
      - Chat
  /api/v1/build_public_tmp/{flow_id}/flow:
    post:
      description: 'Build a public flow without requiring authentication.<br><br>This endpoint is specifically for public flows that don''t require authentication.<br>It uses a client_id cookie to create a deterministic flow ID for tracking purposes.<br><br>Security Note:<br>- The ''data'' parameter is NOT accepted to prevent flow definition tampering<br>- Public flows must execute the stored flow definition only<br>- The flow definition is always loaded from the database<br><br>The endpoint:<br>1. Verifies the requested flow is marked as public in the database<br>2. Creates a deterministic UUID based on client_id and flow_id<br>3. Uses the flow owner''s permissions to build the flow<br>4. Always loads the flow definition from the database<br><br>Requirements:<br>- The flow must be marked as PUBLIC in the database<br>- The request must include a client_id cookie<br><br>Args:<br>    flow_id: UUID of the public flow to build<br>    background_tasks: Background tasks manager<br>    inputs: Optional input values for the flow<br>    files: Optional files to include<br>    stop_component_id: Optional ID of component to stop at<br>    start_component_id: Optional ID of component to start from<br>    log_builds: Whether to log the build process<br>    flow_name: Optional name for the flow<br>    request: FastAPI request object (needed for cookie access)<br>    queue_service: Queue service for job management<br>    authenticated_user: Optional authenticated user (resolved from cookie/token if present)<br>    event_delivery: Optional event delivery type - default is streaming<br><br>Returns:<br>    Dict with job_id that can be used to poll for build status'
      operationId: build_public_tmp_api_v1_build_public_tmp__flow_id__flow_post
      parameters:
      - in: path
        name: flow_id
        required: true
        schema:
          format: uuid
          title: Flow Id
          type: string
      - in: query
        name: stop_component_id
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          title: Stop Component Id
      - in: query
        name: start_component_id
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          title: Start Component Id
      - in: query
        name: log_builds
        required: false
        schema:
          anyOf:
          - type: boolean
          - type: 'null'
          default: true
          title: Log Builds
      - in: query
        name: flow_name
        required: false
        schema:
          anyOf:
          - type: string
          - type: 'null'
          title: Flow Name
      - in: query
        name: event_delivery
        required: false
        schema:
          $ref: '#/components/schemas/EventDeliveryType'
          default: polling
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/Body_build_public_tmp_api_v1_build_public_tmp__flow_id__flow_post'
      responses:
        '200':
          content:
            application/json:
              schema: {}
          description: Successful Response
        '422':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
          description: Validation Error
      summary: Build Public Tmp
      tags:
      - Chat
  /api/v1/build_public_tmp/{job_id}/cancel:
    post:
      description: Cancel a public flow build job.<br><br>This endpoint does not require authentication, matching the public build endpoint.<br>It is used by the shareable playground to cancel builds.
      operationId: cancel_build_public_api_v1_build_public_tmp__job_id__cancel_post
      parameters:
      - in: path
        name: job_id
        required: true
        schema:
          title: Job Id
          type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CancelFlowResponse'
          description: Successful Response
        '422':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
          description: Validation Error
      summary: Cancel Build Public
      tags:
      - Chat
  /api/v1/build_public_tmp/{job_id}/events:
    get:
      description: Get events for a public flow build job.<br><br>This endpoint does not require authentication, matching the public build endpoint.<br>It is used by the shareable playground to consume build events.
      operationId: get_build_events_public_api_v1_build_public_tmp__job_id__events_get
      parameters:
      - in: path
        name: job_id
        required: true
        schema:
          title: Job Id
          type: string
      - in: query
        name: event_delivery
        required: false
        schema:
          $ref: '#/components/schemas/EventDeliveryType'
          default: streaming
      responses:
        '200':
          content:
            application/json:
              schema: {}
          description: Successful Response
        '422':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
          description: Validation Error
      summary: Get Build Events Public
      tags:
      - Chat
components:
  schemas:
    Body_build_public_tmp_api_v1_build_public_tmp__flow_id__flow_post:
      properties:
        files:
          anyOf:
          - items:
              type: string
            type: array
          - type: 'null'
          title: Files
        inputs:
          anyOf:
          - $ref: '#/components/schemas/InputValueRequest'
          - type: 'null'
      title: Body_build_public_tmp_api_v1_build_public_tmp__flow_id__flow_post
      type: object
    HTTPValidationError:
      properties:
        detail:
          items:
            $ref: '#/components/schemas/ValidationError'
          title: Detail
          type: array
      title: HTTPValidationError
      type: object
    ValidationError:
      properties:
        ctx:
          title: Context
          type: object
        input:
          title: Input
        loc:
          items:
            anyOf:
            - type: string
            - type: integer
          title: Location
          type: array
        msg:
          title: Message
          type: string
        type:
          title: Error Type
          type: string
      required:
      - loc
      - msg
      - type
      title: ValidationError
      type: object
    FlowDataRequest:
      properties:
        edges:
          items:
            additionalProperties: true
            type: object
          title: Edges
          type: array
        nodes:
          items:
            additionalProperties: true
            type: object
          title: Nodes
          type: array
        viewport:
          anyOf:
          - additionalProperties: true
            type: object
          - type: 'null'
          title: Viewport
      required:
      - nodes
      - edges
      title: FlowDataRequest
      type: object
    Body_build_flow_api_v1_build__flow_id__flow_post:
      properties:
        data:
          anyOf:
          - $ref: '#/components/schemas/FlowDataRequest'
          - type: 'null'
        files:
          anyOf:
          - items:
              type: string
            type: array
          - type: 'null'
          title: Files
        inputs:
          anyOf:
          - $ref: '#/components/schemas/InputValueRequest'
          - type: 'null'
      title: Body_build_flow_api_v1_build__flow_id__flow_post
      type: object
    InputValueRequest:
      additionalProperties: false
      examples:
      - components:
        - components_id
        - Component Name
        input_value: input_value
        session: session_id
      - components:
        - Component Name
        input_value: input_value
      - input_value: input_value
      - components:
        - Component Name
        input_value: input_value
        session: session_id
      - input_value: input_value
        session: session_id
      - input_value: input_value
        type: chat
      - input_value: '{"key": "value"}'
        type: json
      properties:
        client_request_time:
          anyOf:
          - type: integer
          - type: 'null'
          description: Client-side timestamp in milliseconds when the request was initiated. Used to calculate accurate end-to-end duration.
          title: Client Request Time
        components:
          anyOf:
          - items:
              type: string
            type: array
          - type: 'null'
          default: []
          title: Components
        input_value:
          anyOf:
          - type: string
          - type: 'null'
          title: Input Value
        session:
          anyOf:
          - type: string
          - type: 'null'
          title: Session
        type:
          anyOf:
          - enum:
            - chat
            - text
            - any
            type: string
          - type: 'null'
          default: any
          description: Defines on which components the input value should be applied. 'any' applies to all input components.
          title: Type
      title: InputValueRequest
      type: object
    EventDeliveryType:
      enum:
      - streaming
      - direct
      - polling
      title: EventDeliveryType
      type: string
    CancelFlowResponse:
      description: Response model for flow build cancellation.
      properties:
        message:
          title: Message
          type: string
        success:
          title: Success
          type: boolean
      required:
      - success
      - message
      title: CancelFlowResponse
      type: object
  securitySchemes:
    API key header:
      in: header
      name: x-api-key
      type: apiKey
    API key query:
      in: query
      name: x-api-key
      type: apiKey
    OAuth2PasswordBearerCookie:
      flows:
        password:
          scopes: {}
          tokenUrl: api/v1/login
      type: oauth2
Langflow Chat API

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