> ## Documentation Index > Fetch the complete documentation index at: https://rasa.com/docs/llms.txt > Use this file to discover all available pages before exploring further. # Post user message from a REST channel > Post a message from the user and forward it to the assistant. Return the message of the assistant to the user. ## OpenAPI ````yaml /openapi/pro.yaml post /webhooks/{rest_channel}/webhook openapi: 3.0.1 info: title: Rasa - Server Endpoints version: 1.0.0 description: >- The Rasa server provides endpoints to retrieve trackers of conversations as well as endpoints to modify them. Additionally, endpoints for training and testing models are provided. servers: - url: http://localhost:5005 description: Local development server security: [] paths: /webhooks/{rest_channel}/webhook: post: tags: - Channel Webhooks summary: Post user message from a REST channel description: >- Post a message from the user and forward it to the assistant. Return the message of the assistant to the user. operationId: postMessageRestChannel parameters: - $ref: '#/components/parameters/rest_channel' requestBody: description: The user message payload required: true content: application/json: schema: $ref: '#/components/schemas/BasicMessagePayload' responses: '200': description: The message was processed successfully content: application/json: schema: type: array items: anyOf: - $ref: '#/components/schemas/BotTextMessage' - $ref: '#/components/schemas/BotImageMessage' - $ref: '#/components/schemas/BotButtonsMessage' - $ref: '#/components/schemas/BotAttachmentMessage' '401': $ref: '#/components/responses/401NotAuthenticated' '403': $ref: '#/components/responses/403NotAuthorized' '406': $ref: '#/components/responses/406InvalidHeader' '500': $ref: '#/components/responses/500ServerError' security: - TokenAuth: [] - JWT: [] components: parameters: rest_channel: in: path name: rest_channel description: >- The REST channel used for custom integrations. They provide a URL where you can post messages and either receive response messages directly, or asynchronously via a webhook. required: true schema: type: string enum: - rest - callback schemas: BasicMessagePayload: type: object properties: sender: type: string description: The sender ID example: default message: type: string description: The message text example: Hello! BotTextMessage: type: object properties: recipient_id: type: string description: Id of the message receiver example: default text: type: string description: Message example: Hello! BotImageMessage: type: object properties: recipient_id: type: string description: Id of the message receiver example: default image: type: string description: Image URL example: https://example.com/image.jpg BotButtonsMessage: type: object properties: recipient_id: type: string description: Id of the message receiver example: default buttons: type: array description: Quick reply buttons items: type: object properties: title: type: string description: Button caption payload: type: string description: Payload to be sent if button is clicked example: - title: 'Yes' payload: 'yes' - title: 'No' payload: 'no' BotAttachmentMessage: type: object properties: recipient_id: type: string description: Id of the message receiver example: default attachement: type: array description: Additional information items: type: object properties: title: type: string description: Attachment caption example: Attachment Title payload: type: string description: Attachment payload example: Attachment Payload Error: type: object properties: version: type: string description: Rasa version status: type: string enum: - failure description: Status of the requested action message: type: string description: Error message reason: type: string description: Error category details: type: object description: Additional error information help: type: string description: Optional URL to additonal material code: type: number description: HTTP status code responses: 401NotAuthenticated: description: User is not authenticated. content: application/json: schema: $ref: '#/components/schemas/Error' example: version: 1.0.0 status: failure reason: NotAuthenticated message: User is not authenticated to access resource. code: 401 403NotAuthorized: description: User has insufficient permission. content: application/json: schema: $ref: '#/components/schemas/Error' example: version: 1.0.0 status: failure reason: NotAuthorized message: User has insufficient permission to access resource. code: 403 406InvalidHeader: description: Invalid header provided. content: application/json: schema: $ref: '#/components/schemas/Error' example: version: 1.0.0 status: failure reason: InvalidHeader message: Invalid header was provided with the request. code: 406 500ServerError: description: An unexpected error occurred. content: application/json: schema: $ref: '#/components/schemas/Error' example: version: 1.0.0 status: ServerError message: An unexpected error occurred. code: 500 securitySchemes: TokenAuth: type: apiKey in: query name: token description: > A plaintext token to secure your server, specified at startup in the argument `--auth-token thisismysecret` JWT: type: http scheme: bearer bearerFormat: JWT description: > A JWT token that is signed using the JWT secret specified at startup in the argument `--jwt-secret thisismysecret`, using the `HS256` algorithm. The token's payload must contain an object under the `user` key, which in turn must contain the `username` and `role` attributes. The following is an example payload for a JWT token: ```json { "user": { "username": "", "role": "user" } } ``` If the `role` is `admin`, all endpoints are accessible. If the `role` is `user`, endpoints with a `sender_id` parameter are only accessible if the `sender_id` matches the payload's `username` property. For the user trackers endpoint (`GET /users/{user_id}/trackers`), you should use `user_id` instead of `username` in the payload. In this case, the path `user_id` parameter is matched against the payload's `username` property. For example: ```json { "user": { "username": "", "role": "user" } } ``` ````