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OpenAPI Specification

openapi: 3.2.0
info:
  title: Flow Wait for Callback API
  version: 1.1.0
  x-provenance:
    method: searched
    source: https://help.clickatell.com/developers-api-reference/ (OpenAPI fragments embedded verbatim in the GitBook .md twins, merged by info.title)
    generated: '2026-10-13'
servers:
- url: https://flow-callback.clickatell.com/
  description: Production server
- url: https://control-callback-uat.payd.co/
  description: Sandbox/UAT server
tags:
- name: Wait for Callback
paths:
  /chat/callback:
    post:
      tags:
      - Wait for Callback
      summary: Wait for an external system to initiate a callback
      description: 'The Wait for Callback node was created to facilitate an asynchronous process external to Chat Flow. For example waiting for an external client system to generate an invoice.


        This node will block the flow until a callback was received or the timed out was reached. The timeout is 1 minute less that the session length.


        This node should be used in conjunction with the Set Variable Node to first set a UUID as a variable and then use that UUID in the Reference Field on the node and in the Callback API so that the Callback Handler can identify that the callback belong to a specific session.


        Once the callback is received the end-user can then continue with the conversational workflow according to the steps defined in Flow.'
      parameters:
      - name: reference
        in: header
        description: A reference to be passed as a header.
        required: true
        schema:
          type: string
      requestBody:
        description: Payload describing the callback result
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/Waitforcallback'
      responses:
        '202':
          description: Successfully validated the response and returned data appended to matched session.
        '204':
          description: Callback has previously been processed in is being ignored.
        '400':
          description: A bad/invalid reference was returned and the session could not be matched, or the session has expired.
      operationId: postChatCallback
      x-operation-id-source: derived
components:
  schemas:
    Waitforcallback:
      type: object