> ## Documentation Index > Fetch the complete documentation index at: https://docs.watahub.dev/llms.txt > Use this file to discover all available pages before exploring further. # Send a message with Meta's request and response > Send a message with Meta's request and response ## OpenAPI ````yaml openapi.json POST /v{graphVersion}/{phoneNumberId}/messages openapi: 3.1.0 info: title: Watahub API version: 0.2.0 description: >- Tenant API of Watahub, the multi-tenant WhatsApp Cloud API gateway. Authenticate every request with your API key as `Authorization: Bearer ` or `X-API-Key: `. - Shapes the gateway owns are closed: no other field appears. - Records that come from Meta are open: documented fields are listed and any other field Meta adds is passed through. - The `/vN.N` proxy passes Meta's body and status through untouched; the version in the path is accepted and ignored. servers: - url: https://cloud.watahub.dev security: - bearerApiKey: [] - headerApiKey: [] tags: - name: Messages - name: Media - name: Templates - name: Graph-compatible proxy description: >- Drop-in for Meta's Graph API on three routes. Meta's response is returned as is. - name: Phones description: Phones - name: Conversations description: Conversations - name: Connect description: Connect - name: Customers description: Customers - name: Webhooks description: Webhooks - name: Logs description: Logs - name: Health description: Health - name: Message templates description: >- Templates cached by the gateway per WABA; synced from Meta and required by broadcasts. - name: Broadcasts description: >- Send one approved template to up to 500 recipients; sending is queued and drained in the background. paths: /v{graphVersion}/{phoneNumberId}/messages: post: tags: - Graph-compatible proxy summary: Send a message with Meta's request and response description: >- The body goes to Meta's `/messages` unchanged and Meta's answer comes back unchanged. operationId: postVgraphVersionPhoneNumberIdMessages parameters: - $ref: '#/components/parameters/GraphVersion' - name: phoneNumberId in: path required: true schema: $ref: '#/components/schemas/GraphId' responses: '200': description: Meta's answer. content: application/json: schema: $ref: '#/components/schemas/GraphSendResult' 4XX: $ref: '#/components/responses/GraphClientError' 5XX: $ref: '#/components/responses/GraphSendServerError' components: parameters: GraphVersion: name: graphVersion in: path required: true description: >- Any `N.N`. Ignored: Graph is called with the gateway's `META_API_VERSION`. schema: type: string pattern: ^\d+\.\d+$ schemas: GraphId: type: string pattern: ^\d+$ description: Numeric Meta Graph ID. GraphSendResult: type: object description: Meta's answer to a send. additionalProperties: true required: - messaging_product - contacts - messages properties: messaging_product: const: whatsapp contacts: type: array items: type: object additionalProperties: true properties: input: type: string wa_id: type: string messages: type: array items: type: object additionalProperties: true required: - id properties: id: type: string description: The wamid. message_status: type: string description: Such as `accepted`, `held_for_quality_assessment` or `paused`. GatewayError: type: object description: >- An error the gateway or the core answers itself. `error` is a stable English message for developers. additionalProperties: false required: - error properties: error: type: string fields: type: array items: type: string description: 'With 400 `Invalid fields`: the paths of the rejected fields.' requestId: type: string description: 'With 500 `Operation unavailable`: the ID to quote to support.' GraphError: type: object description: Meta's error body, unchanged. additionalProperties: true required: - error properties: error: type: object additionalProperties: true required: - message - code properties: message: type: string type: type: string code: type: integer error_subcode: type: integer error_user_title: type: string error_user_msg: type: string error_data: type: object additionalProperties: true fbtrace_id: type: string MetaError: type: object description: >- Meta failed a `/v1` call. With Meta's error: `code`, its `subcode`, `type` on sends, and the core's classification. When Meta could not be reached or answered something unusable, only `message`, plus the `unknown_outcome` classification on sends. additionalProperties: false required: - error properties: error: type: object additionalProperties: false required: - message properties: message: type: string code: type: integer description: Meta's error code; Meta's HTTP status when Meta gave none. subcode: type: integer description: Meta's `error_subcode`. type: type: string description: Meta's error type. Only on message sends. category: type: string enum: - auth - billing - rate_limit - meta_server - unknown - unknown_outcome retryable: type: boolean action: type: string description: What to do next, in English. responses: GraphClientError: description: >- Rejected by the gateway (`GatewayError`) or by Meta (`GraphError`, Meta's body and status). content: application/json: schema: anyOf: - $ref: '#/components/schemas/GatewayError' - $ref: '#/components/schemas/GraphError' GraphSendServerError: description: >- As `GraphServerError`. The message may have been sent: confirm it with the status webhook before retrying. headers: X-Watahub-Outcome: description: '`unknown` when Meta answered the send with a 5XX.' schema: type: string enum: - unknown content: application/json: schema: anyOf: - $ref: '#/components/schemas/GatewayError' - $ref: '#/components/schemas/MetaError' - $ref: '#/components/schemas/GraphError' securitySchemes: bearerApiKey: type: http scheme: bearer description: Tenant API key. headerApiKey: type: apiKey in: header name: X-API-Key description: Tenant API key. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.