> ## Documentation Index > Fetch the complete documentation index at: https://docs.conduit.ai/llms.txt > Use this file to discover all available pages before exploring further. # Send Contact Message > Delivers a new outbound message through the exact `channel_node_id` chosen for the contact. ## OpenAPI ````yaml POST /v1/contacts/{id}/messages openapi: 3.0.0 info: title: Conduit API version: 1.0.0 description: Public API for Conduit. servers: - url: https://api.conduit.ai description: Production security: [] tags: - name: meta description: Discovery and API metadata endpoints. - name: agents description: >- V2 chat agent configuration, including instructions, skills, triggers, and automation behavior. - name: contacts description: >- Contact profile and contact-scoped related resources such as tickets and calls. - name: workspaces description: Workspaces accessible to the current API token. - name: escalations description: >- Chat escalations that require operator review, including message, proposed response, and disposition context when available. - name: conversations description: >- Canonical message threads. Use these endpoints to list threads, inspect conversation state, read transcripts, and send replies. - name: conversation-tags description: >- Conversation labels, root topics, and subtopics used for classification and topic analytics. - name: tickets description: >- Operational queue items tied to conversations, including ticket-scoped transcripts and replies. - name: calls description: Phone call records, transcripts, summaries, and recordings when available. - name: reservations description: >- PMS reservations synced from the workspace's integrations (Hostaway, Guesty, Airbnb, etc.), including guest identity, payment status, and stay dates. - name: appointments description: >- Scheduled appointments (bookings) backed by the Conduit booking service. Exposes allocation context and the upstream booking-service `external_id`. - name: helpdesk_tickets description: >- Helpdesk tickets mirrored from external helpdesk integrations (Zendesk, Pylon, Plain), including requester identity and upstream metadata. - name: kb description: >- Knowledge base search and node management. Nodes represent knowledge base entries (files or directories), chunks are the indexed retrieval units used by search. - name: skills description: >- Workspace agent skills that can be attached to V2 chat agents. Sidebar/global-assistant skills are intentionally excluded. - name: custom_tools description: >- Custom code tools: user-authored Python/JavaScript functions executed in a sandbox when an agent calls them. Includes a runtimes endpoint describing the entrypoint signature, return shape, and available dependencies per language. - name: inbox_types description: >- Workspace inbox types. Each id is stable and usable as a message trigger's `inboxTypeId` and as the `inbox_type_id` filter on list conversations. - name: workflows description: >- Workspace automation workflows: definitions, executions, and per-execution event timelines. - name: insights description: Aggregated workspace analytics, such as conversation automation rate. paths: /v1/contacts/{id}/messages: post: tags: - contacts summary: Send a proactive message to a contact description: >- Delivers a new outbound message through the exact `channel_node_id` chosen for the contact. Supply `sender_id` when you need to choose the exact workspace sender returned by `/v1/workspaces/{id}/senders`. operationId: sendContactMessage parameters: - schema: type: string description: Contact id. example: ph77c0dy0mgdpzmqz6tesry8w184002s required: true name: id in: path - schema: type: string description: >- Optional workspace override. If omitted, Conduit resolves the contact's workspace automatically. example: j57demo8f8x7c9v0n2q4r6t8y1u3i5o required: false name: workspace_id in: query requestBody: required: true content: application/json: schema: type: object properties: channel_node_id: type: string description: Exact contact channel node to deliver through. sender_id: type: string description: >- Optional workspace sender to use. Required when multiple compatible senders exist and no single default can be chosen. body: type: string minLength: 1 description: >- Plain-text message body. Required unless `whatsapp_template` is provided. subject: type: string description: Optional subject for email channel nodes. whatsapp_template: type: object properties: content_sid: type: string minLength: 1 description: >- Twilio Content SID for an approved WhatsApp template returned by `/v1/workspaces/{id}/whatsapp-templates`. variables: type: object additionalProperties: type: string description: >- Template variable values keyed by Twilio variable name, for example `{ "1": "Alex" }`. required: - content_sid description: >- WhatsApp template to send instead of a plain-text body. Only valid for WhatsApp channel nodes. required: - channel_node_id description: >- Request body for sending a proactive message to a contact through an explicit channel node. Provide either `body` for plain text or `whatsapp_template` for a WhatsApp template send. example: channel_node_id: hg77c0dy0mgdpzmqz6tesry8w184002s sender_id: whatsapp_number:+14155550999 whatsapp_template: content_sid: HXaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa variables: '1': Alex '2': May 15 at 3 PM responses: '201': description: Contact message accepted content: application/json: schema: type: object properties: data: type: object properties: id: type: string nullable: true workspace_id: type: string contact_id: type: string channel_node_id: type: string sender_id: type: string channel: type: string status: type: string enum: - sent required: - id - workspace_id - contact_id - channel_node_id - sender_id - channel - status required: - data description: >- Result returned after a proactive contact message is accepted for delivery. example: data: id: yh7t5azsr0zpfpyf67vtce0j6n844y1e workspace_id: j57demo8f8x7c9v0n2q4r6t8y1u3i5o contact_id: ph77c0dy0mgdpzmqz6tesry8w184002s channel_node_id: hg77c0dy0mgdpzmqz6tesry8w184002s sender_id: gmail_account:team@conduit.ai channel: email status: sent '400': description: Invalid request content: application/json: schema: type: object properties: error: type: string required: - error description: Standard error response. example: error: Invalid workspace id '401': description: Unauthorized content: application/json: schema: type: object properties: error: type: string required: - error description: Standard error response. example: error: Invalid workspace id '403': description: Forbidden content: application/json: schema: type: object properties: error: type: string required: - error description: Standard error response. example: error: Invalid workspace id '404': description: Not found content: application/json: schema: type: object properties: error: type: string required: - error description: Standard error response. example: error: Invalid workspace id '409': description: Conflict content: application/json: schema: type: object properties: error: type: string required: - error description: Standard error response. example: error: Invalid workspace id '429': description: Rate limit exceeded content: application/json: schema: type: object properties: error: type: string required: - error description: Standard error response. example: error: Invalid workspace id '500': description: Internal error content: application/json: schema: type: object properties: error: type: string required: - error description: Standard error response. example: error: Invalid workspace id '503': description: Service unavailable content: application/json: schema: type: object properties: error: type: string required: - error description: Standard error response. example: error: Invalid workspace id security: - bearerAuth: [] components: securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: API Token description: >- Conduit API token. Use `Authorization: Bearer `. Read/write endpoints require a token with write access. ````