> ## Documentation Index > Fetch the complete documentation index at: https://developers.conveyour.com/llms.txt > Use this file to discover all available pages before exploring further. # Create a message > Sends a message to a contact. Set `class` to `"sms"` or `"email"` to control the delivery channel, and identify the recipient with `type: "contact"` + `type_id` (the contact's ID). There is **no `contact_id` field** on this endpoint — a posted `contact_id` is silently dropped and the message will fail to resolve a recipient. Address the message with `type: "contact"` and `type_id: ""` instead. Send an SMS or email to a contact ## OpenAPI ````yaml /api-reference/specs/messages.json post /api/messages openapi: 3.1.0 info: title: ConveYour API — Messages description: >- Send SMS and email messages to contacts, and manage conversation thread assignments. version: 1.0.0 servers: - url: https://{subdomain}.conveyour.com description: Your organization's ConveYour instance variables: subdomain: default: acme description: >- Your organization's slug — the subdomain you sign in on. Replace `acme` with yours: if you sign in at `bigco.conveyour.com`, enter `bigco`. security: - conveyourToken: [] tags: - name: Messages description: >- Send SMS and email messages to contacts, and manage conversation thread assignments. paths: /api/messages: post: tags: - Messages summary: Create a message description: >- Sends a message to a contact. Set `class` to `"sms"` or `"email"` to control the delivery channel, and identify the recipient with `type: "contact"` + `type_id` (the contact's ID). There is **no `contact_id` field** on this endpoint — a posted `contact_id` is silently dropped and the message will fail to resolve a recipient. Address the message with `type: "contact"` and `type_id: ""` instead. Send an SMS or email to a contact operationId: sendAnSmsOrEmailToAContact parameters: - $ref: '#/components/parameters/teams' requestBody: required: true content: application/json: schema: type: object required: - class - type - type_id - body properties: class: description: The delivery channel. Either `"sms"` or `"email"`. type: string type: description: >- The recipient type. Use `"contact"` to send to a single contact. (Other values: `bookmark`, `trigger`, `campaign`, `trigger_lesson`, `trigger_wait`.) type: string type_id: description: >- The ID of the recipient. When `type` is `"contact"`, this is the contact's ID. type: string body: description: >- The message body. Supports [Liquid syntax](/guides/liquid-syntax) for personalization. type: string subject: description: >- Email subject line. Required when `class` is `"email"`. Supports Liquid syntax. type: string close: type: boolean default: false description: Close the conversation thread after sending. inherit_thread_close_state: type: boolean default: false description: >- Adopt the thread's existing closed state instead of setting it explicitly. responses: '200': description: Success. content: application/json: schema: allOf: - $ref: '#/components/schemas/Envelope' - type: object properties: data: $ref: '#/components/schemas/CreatedMessageRef' example: status: ok message: Message created data: id: 64a1b2c3d4e5f6a7b8c9d0e1 time: just now '403': $ref: '#/components/responses/Forbidden' '429': description: >- Send limit reached. Errors filtered by code 429 from the message class — the SMS or email quota for the org. This cannot be caught by the pre-flight `limitCheck()`, because that check cannot know how many contacts the new message targets. `data` carries the usage overview for the `sms` or `emails` limit. content: application/json: schema: type: object properties: status: type: string enum: - failed description: Always `failed`. message: type: string description: Human-readable explanation. data: type: object description: >- Usage overview for the limit that was hit — used, unused and overage counts. components: parameters: teams: name: teams[] in: query description: >- Team scope for the request, as one or more team ObjectIds. The brackets are required: PHP keeps only the last value for a repeated plain key, so `teams=A&teams=B` silently resolves to B alone. On requests with a JSON body you may send `teams` (no brackets) in the body instead. **Values that are not valid ObjectIds are silently ignored** — a mistyped team ID behaves as if no team was sent. See the [teams section of the API conventions guide](/guides/api-conventions#team-scoping). style: form explode: true schema: type: array items: type: string example: - 64a1b2c3d4e5f6a7b8c9d0ff schemas: Envelope: type: object description: The common response envelope shared by all ConveYour endpoints. properties: status: type: string enum: - ok - failed description: '`ok` on success, `failed` on error.' message: type: string description: Human-readable description of the result. data: description: >- The response payload — an object or an array depending on the endpoint. CreatedMessageRef: type: object description: >- Create returns only an id and a fixed placeholder time — not the message record. properties: id: type: string description: ID of the new message. time: type: string enum: - just now description: >- Always the literal string 'just now' — it is hardcoded, not a timestamp. required: - id - time responses: Forbidden: description: >- The token is missing or invalid, or the service account behind it lacks the permission this endpoint requires. content: application/json: example: status: failed message: Lacking necessary permission add_contacts data: permission: add_contacts securitySchemes: conveyourToken: type: apiKey in: header name: x-conveyour-token description: >- Your API key token. Contacts endpoints require a **Server-only — Full API** key — see [Authentication](/quickstart). ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.