> ## Documentation Index > Fetch the complete documentation index at: https://docs.artil.ai/llms.txt > Use this file to discover all available pages before exploring further. # Send a message > Answer a message by giving its id as replyTo, start a new one with a channel and recipients in to, or pass one on by giving its id as forward and recipients in to. ## OpenAPI ````yaml /openapi.json post /agents/{id}/messages openapi: 3.1.0 info: title: Artil API description: Give AI agents their own email inbox, SMS number and secret storage. version: 1.0.0 servers: - url: https://app.artil.ai/api security: - token: [] paths: /agents/{id}/messages: post: tags: - Messages summary: Send a message description: >- Answer a message by giving its id as replyTo, start a new one with a channel and recipients in to, or pass one on by giving its id as forward and recipients in to. operationId: sendMessage parameters: - in: path name: id required: true description: The agent's id schema: type: string format: uuid requestBody: required: true content: application/json: schema: type: object properties: replyTo: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ forward: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ channel: type: string enum: - email - sms - telegram to: minItems: 1 maxItems: 10 type: array items: type: string minLength: 1 maxLength: 320 cc: maxItems: 50 type: array items: type: string minLength: 1 maxLength: 320 subject: type: string maxLength: 240 text: type: string minLength: 1 maxLength: 32000 required: - text responses: '201': description: The sent message content: application/json: schema: $ref: '#/components/schemas/Message' default: $ref: '#/components/responses/Failure' components: schemas: Message: type: object properties: id: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ addressId: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ description: The agent's address the message came to or went from channel: type: string enum: - email - sms - telegram direction: type: string enum: - inbound - outbound counterpart: type: string description: Who sent an inbound message, or the recipients of an outbound one counterpartName: description: >- The name an inbound message's sender goes by, when the channel tells it type: - string - 'null' to: type: array items: type: string description: >- Whom the message names as its recipients; an inbound one names the agent unless it got a blind copy cc: type: array items: type: string description: Whom the message names as getting a copy subject: type: - string - 'null' text: type: string attachments: type: array items: type: object properties: name: type: string type: type: string size: type: number required: - name - type - size thread: anyOf: - type: object properties: messageId: type: string references: type: array items: type: string required: - messageId - references - type: 'null' description: >- For received and imported email, its Message-ID and References; for email the agent sent, those of the email it answered status: type: string enum: - received - refused - sending - sent - failed - imported - reported description: '`reported` when the recipient marked an email the agent sent as spam' refusal: anyOf: - type: string enum: - self - spam - plan_limit - rate_limit - sender - outsider - unverified - type: 'null' description: Why a refused message did not wake the agent admission: anyOf: - type: string enum: - team - listed - anyone - type: 'null' description: >- Who the sender of a received message is to the agent: `team` for a member or agent of the workspace, `listed` for a sender on the channel's list, and `anyone` for everyone else, including senders who could not be verified error: description: Why a failed message was not sent or did not arrive type: - string - 'null' createdAt: type: string format: date-time required: - id - addressId - channel - direction - counterpart - counterpartName - to - cc - subject - text - attachments - thread - status - refusal - admission - error - createdAt responses: Failure: description: The request failed; the error says why content: application/json: schema: type: object properties: error: type: object properties: code: type: string enum: - invalid_input - unauthorized - forbidden - plan_limit - not_found - conflict - rate_limited - internal - unavailable message: type: string required: - code - message required: - error securitySchemes: token: type: http scheme: bearer ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.