Klaviyo Conversations API

openapi: 3.0.2
info:
  title: Klaviyo Accounts Conversations API
  version: '2026-04-15'
  description: The Klaviyo REST API. Please visit https://developers.klaviyo.com for more details.
  contact:
    name: Klaviyo Developer Experience Team
    email: developers@klaviyo.com
    url: https://developers.klaviyo.com
  termsOfService: https://www.klaviyo.com/legal/api-terms
  license:
    name: License
    url: https://www.klaviyo.com/legal
servers:
- url: https://a.klaviyo.com
  description: Production
security:
- Klaviyo-API-Key: []
tags:
- name: Conversations
  description: conversations
paths:
  /api/conversation-messages:
    post:
      operationId: create_conversation_message
      summary: Create Conversation Message
      description: 'Send an outbound message to a conversation.


        Requires OAuth authentication and account-level enablement. To request access, reach out in the [developer community](https://community.klaviyo.com/groups/developer-group-64).<br><br>*Rate limits*:<br>Burst: `3/s`<br>Steady: `60/m`


        **Scopes:**

        `conversations:write`'
      parameters:
      - name: revision
        in: header
        description: 'API endpoint revision (format: YYYY-MM-DD[.suffix])'
        required: true
        schema:
          type: string
          default: '2026-04-15'
      requestBody:
        description: Create a conversation message
        required: true
        content:
          application/vnd.api+json:
            schema:
              $ref: '#/components/schemas/ConversationMessageCreateQuery'
      responses:
        '202':
          description: Success
        4XX:
          $ref: '#/components/responses/ClientError'
        5XX:
          $ref: '#/components/responses/ServerError'
      tags:
      - Conversations
      x-klaviyo-pre-release: None
      x-klaviyo-ratelimit:
        burst: 3/s
        steady: 60/m
      x-klaviyo-scopes:
      - conversations:write
components:
  schemas:
    ConversationMessageCreateQuery:
      type: object
      properties:
        data:
          $ref: '#/components/schemas/ConversationMessageCreateQueryResourceObject'
      required:
      - data
    ConversationMessageCreateQueryResourceObject:
      type: object
      properties:
        type:
          $ref: '#/components/schemas/ConversationMessageEnum'
        attributes:
          type: object
          properties:
            body:
              type: string
          required:
          - body
        relationships:
          type: object
          properties:
            conversation:
              type: object
              properties:
                data:
                  type: object
                  properties:
                    type:
                      $ref: '#/components/schemas/ConversationEnum'
                    id:
                      description: Related Conversation
                      type: string
                  required:
                  - type
                  - id
          required:
          - conversation
      required:
      - type
      - attributes
      - relationships
    ConversationEnum:
      type: string
      enum:
      - conversation
    ConversationMessageEnum:
      type: string
      enum:
      - conversation-message
  responses:
    ClientError:
      description: Client Error
      content:
        application/vnd.api+json:
          schema:
            type: object
            properties:
              errors:
                type: array
                items:
                  type: object
                  required:
                  - id
                  - code
                  - title
                  - detail
                  properties:
                    id:
                      type: string
                    code:
                      type: string
                    title:
                      type: string
                    detail:
                      type: string
                    source:
                      type: object
                      properties:
                        pointer:
                          type: string
                        parameter:
                          type: string
            required:
            - errors
    ServerError:
      description: Server Error
      content:
        application/vnd.api+json:
          schema:
            type: object
            properties:
              errors:
                type: array
                items:
                  type: object
                  required:
                  - id
                  - code
                  - title
                  - detail
                  properties:
                    id:
                      type: string
                    code:
                      type: string
                    title:
                      type: string
                    detail:
                      type: string
                    source:
                      type: object
                      properties:
                        pointer:
                          type: string
                        parameter:
                          type: string
            required:
            - errors
  securitySchemes:
    Klaviyo-API-Key:
      type: apiKey
      in: header
      name: Authorization
      description: Private key authentication for /api/ endpoints is performed by setting the `Authorization` header to `Klaviyo-API-Key your-private-api-key`<br>For more information please visit https://developers.klaviyo.com/en/v2026-04-15/reference/api-overview#authentication
      x-default: Klaviyo-API-Key your-private-api-key
x-readme:
  explorer-enabled: false
  proxy-enabled: true
  samples-enabled: true