Voiceflow

Voiceflow Session API

Start a session and emit session events.

Documentation GitHub OpenAPI

Operations 2

POST /v2/state/user/{userID}/session/start Start a new session (v4) #

POST /v2/state/user/{userID}/session/emit Emit a session event #

Specifications

⚙

OpenAPI

https://raw.githubusercontent.com/api-evangelist/voiceflow/refs/heads/main/openapi/voiceflow-session-api-openapi.yml

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Voiceflow Conversations Interact Session API
  version: 1.0.0
  summary: REST + SSE API for running Voiceflow agent turns and managing session state.
  description: 'The Voiceflow Conversations API (formerly Dialog Manager API) enables programmatic

    interaction with Voiceflow agents — running turns, managing session state, and

    modifying conversation variables.


    Documentation: https://docs.voiceflow.com/reference

    '
  contact:
    name: Voiceflow Docs
    url: https://docs.voiceflow.com/reference
servers:
- url: https://general-runtime.voiceflow.com
  description: Voiceflow general runtime
security:
- apiKey: []
tags:
- name: Session
  description: Start a session and emit session events.
paths:
  /v2/state/user/{userID}/session/start:
    post:
      tags:
      - Session
      summary: Start a new session (v4)
      operationId: startSession
      parameters:
      - $ref: '#/components/parameters/UserID'
      requestBody:
        required: false
        content:
          application/json:
            schema:
              type: object
              additionalProperties: true
      responses:
        '200':
          description: Session started
  /v2/state/user/{userID}/session/emit:
    post:
      tags:
      - Session
      summary: Emit a session event
      operationId: emitSessionEvent
      parameters:
      - $ref: '#/components/parameters/UserID'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - event
              properties:
                event:
                  type: object
                  required:
                  - name
                  properties:
                    name:
                      type: string
                    payload:
                      type: object
                      additionalProperties: true
      responses:
        '200':
          description: Event accepted
components:
  parameters:
    UserID:
      name: userID
      in: path
      required: true
      schema:
        type: string
      description: Stable identifier for the end user / conversation participant.
  securitySchemes:
    apiKey:
      type: apiKey
      in: header
      name: Authorization
      description: 'Voiceflow Dialog Manager API key (format `VF.DM.*`) sent in the

        `Authorization` header.

        '