Layercode Sessions API

openapi: 3.0.1
info:
  title: Layercode REST API
  description: >-
    REST API for the Layercode voice-AI agent platform. Manage agents
    (voice pipelines), authorize browser client sessions, retrieve session
    detail and recordings, and initiate outbound phone calls. All requests
    are authenticated with an org-scoped API key passed as a Bearer token.
  termsOfService: https://layercode.com/terms
  contact:
    name: Layercode Support
    url: https://docs.layercode.com
  version: '1.0'
servers:
  - url: https://api.layercode.com/v1
security:
  - bearerAuth: []
paths:
  /agents:
    get:
      operationId: listAgents
      tags:
        - Agents
      summary: List agents
      description: Returns all voice agents (pipelines) in the organization.
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: object
                properties:
                  agents:
                    type: array
                    items:
                      $ref: '#/components/schemas/Agent'
    post:
      operationId: createAgent
      tags:
        - Agents
      summary: Create an agent
      description: Creates a new voice agent, optionally from a template.
      requestBody:
        required: false
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateAgentRequest'
      responses:
        '201':
          description: Created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Agent'
  /agents/{agent_id}:
    get:
      operationId: getAgent
      tags:
        - Agents
      summary: Get an agent
      parameters:
        - $ref: '#/components/parameters/AgentId'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Agent'
    post:
      operationId: updateAgent
      tags:
        - Agents
      summary: Update an agent
      description: Updates mutable agent fields such as name and webhook URL.
      parameters:
        - $ref: '#/components/parameters/AgentId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/UpdateAgentRequest'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Agent'
  /agents/web/authorize_session:
    post:
      operationId: authorizeSession
      tags:
        - Sessions
      summary: Authorize a browser client session
      description: >-
        Called from your backend with an agent_id and your org-scoped API key.
        Returns a short-lived client_session_key the browser uses to open the
        realtime WebSocket, plus the conversation_id.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/AuthorizeSessionRequest'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/AuthorizeSessionResponse'
  /agents/{agent_id}/sessions/{session_id}:
    get:
      operationId: getSession
      tags:
        - Sessions
      summary: Get session detail
      description: >-
        Returns metadata, transcript, duration, and recording status for a
        single conversation session handled by the agent.
      parameters:
        - $ref: '#/components/parameters/AgentId'
        - $ref: '#/components/parameters/SessionId'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Session'
  /agents/{agent_id}/sessions/{session_id}/recording:
    get:
      operationId: getSessionRecording
      tags:
        - Sessions
      summary: Download session recording
      description: Returns the WAV audio recording for the session, when available.
      parameters:
        - $ref: '#/components/parameters/AgentId'
        - $ref: '#/components/parameters/SessionId'
      responses:
        '200':
          description: OK
          content:
            audio/wav:
              schema:
                type: string
                format: binary
  /agents/{agent_id}/calls/initiate_outbound:
    post:
      operationId: initiateOutboundCall
      tags:
        - Calls
      summary: Initiate an outbound call
      description: >-
        Places an outbound phone call from an assigned phone number to a
        destination number, connecting the callee to the voice agent.
      parameters:
        - $ref: '#/components/parameters/AgentId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/InitiateOutboundRequest'
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/InitiateOutboundResponse'
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: Org-scoped Layercode API key passed as a Bearer token.
  parameters:
    AgentId:
      name: agent_id
      in: path
      required: true
      description: The unique identifier of the agent.
      schema:
        type: string
    SessionId:
      name: session_id
      in: path
      required: true
      description: The unique identifier of the session (conversation).
      schema:
        type: string
  schemas:
    Agent:
      type: object
      properties:
        id:
          type: string
        name:
          type: string
        type:
          type: string
          description: Agent transport type, e.g. web or phone.
        config:
          type: object
          description: Voice pipeline configuration (STT, TTS, turn-taking).
          additionalProperties: true
        webhook_url:
          type: string
        webhook_secret:
          type: string
        agent_template_id:
          type: string
        assigned_phone_numbers:
          type: array
          items:
            type: string
        created_at:
          type: string
          format: date-time
        updated_at:
          type: string
          format: date-time
    CreateAgentRequest:
      type: object
      properties:
        template_id:
          type: string
          description: Optional agent template to base the new agent on.
        name:
          type: string
    UpdateAgentRequest:
      type: object
      properties:
        name:
          type: string
        webhook_url:
          type: string
    AuthorizeSessionRequest:
      type: object
      required:
        - agent_id
      properties:
        agent_id:
          type: string
        conversation_id:
          type: string
          description: Optional existing conversation to resume.
        config:
          type: object
          description: Optional per-session overrides.
          additionalProperties: true
    AuthorizeSessionResponse:
      type: object
      properties:
        client_session_key:
          type: string
          description: Short-lived key the browser uses to open the WebSocket.
        conversation_id:
          type: string
        config:
          type: object
          additionalProperties: true
    Session:
      type: object
      properties:
        session_id:
          type: string
        agent_id:
          type: string
        conversation_id:
          type: string
        started_at:
          type: string
          format: date-time
        ended_at:
          type: string
          format: date-time
        duration_ms:
          type: integer
        metadata:
          type: object
          additionalProperties: true
        from_phone_number:
          type: string
        to_phone_number:
          type: string
        transcript:
          type: array
          items:
            $ref: '#/components/schemas/TranscriptEntry'
        recording_status:
          type: string
        recording_url:
          type: string
    TranscriptEntry:
      type: object
      properties:
        role:
          type: string
          enum:
            - user
            - assistant
        text:
          type: string
        timestamp:
          type: string
          format: date-time
    InitiateOutboundRequest:
      type: object
      required:
        - from_phone_number
        - to_phone_number
      properties:
        from_phone_number:
          type: string
          description: An assigned Layercode phone number to call from.
        to_phone_number:
          type: string
          description: The destination phone number to dial.
      additionalProperties: true
    InitiateOutboundResponse:
      type: object
      properties:
        conversation_id:
          type: string