> ## Documentation Index > Fetch the complete documentation index at: https://docs.enginy.ai/llms.txt > Use this file to discover all available pages before exploring further. # Send inbox message > Send a manual inbox reply through Enginy conversation routing. Required body fields: - contactId: contact whose thread should receive the reply. - senderIdentityId: sender identity that owns the target thread. - message: plain-text body of the manual reply. Optional body fields: - type: channel used to select the matching conversation. Allowed values are EMAIL and LINKEDIN. If omitted, Enginy falls back to the latest replyable message channel on the matched thread. - attachment: one attachment with url, name, and MIME type. - requestId: idempotency suffix for safely retrying the same manual reply. > **Required scope:** `MESSAGING_WRITE` > > **Rate limit:** 30 requests per minute ## OpenAPI ````yaml https://openapi.enginy.ai/definitions.json post /v1/inbox/messages openapi: 3.1.0 info: title: Enginy API version: 1.0.0 description: Public API for Enginy platform servers: - url: https://openapi.enginy.ai description: Configured server security: [] tags: - name: AI Variables description: >- Manage AI variables and discover the entity fields you can reference in prompts and entity requests. - name: Inbox description: >- Inbox endpoints for listing contact threads, reading thread messages, managing tags, and sending manual replies. - name: Workflows description: >- Build, validate, publish, run, and inspect advanced (graph) workflows, plus the block/condition catalog needed to author a workflow plan. paths: /v1/inbox/messages: post: tags: - Inbox summary: Send inbox message description: >- Send a manual inbox reply through Enginy conversation routing. Required body fields: - contactId: contact whose thread should receive the reply. - senderIdentityId: sender identity that owns the target thread. - message: plain-text body of the manual reply. Optional body fields: - type: channel used to select the matching conversation. Allowed values are EMAIL and LINKEDIN. If omitted, Enginy falls back to the latest replyable message channel on the matched thread. - attachment: one attachment with url, name, and MIME type. - requestId: idempotency suffix for safely retrying the same manual reply. > **Required scope:** `MESSAGING_WRITE` > > **Rate limit:** 30 requests per minute requestBody: required: true content: application/json: schema: type: object properties: contactId: type: integer exclusiveMinimum: 0 description: Contact ID to reply to example: 123 senderIdentityId: type: integer exclusiveMinimum: 0 description: Sender identity ID that owns the conversation example: 14 type: type: string enum: - EMAIL - LINKEDIN description: >- Optional channel to use when selecting the matching conversation. Defaults to the last replyable message channel example: EMAIL message: type: string minLength: 1 description: Reply message content example: >- Absolutely. I just sent over our pricing breakdown and can walk through it live if helpful. attachment: type: object properties: url: type: string format: uri description: Attachment URL example: https://cdn.enginy.ai/files/pricing-one-pager.pdf name: type: string minLength: 1 description: Attachment name example: pricing-one-pager.pdf type: type: string minLength: 1 description: Attachment MIME type example: application/pdf required: - url - name - type description: >- Optional single attachment supported by the manual reply flow requestId: type: string minLength: 1 description: Optional idempotency key suffix for the manual reply example: manual-reply-20260320-001 required: - contactId - senderIdentityId - message examples: basicEmailReply: summary: Reply on an email thread value: contactId: 123 senderIdentityId: 14 type: EMAIL message: >- Absolutely. I just sent over our pricing breakdown and can walk through it live if helpful. requestId: manual-reply-20260320-001 emailReplyWithAttachment: summary: Reply on an email thread with one attachment value: contactId: 123 senderIdentityId: 14 type: EMAIL message: Sharing the pricing one-pager here as well. attachment: url: https://cdn.enginy.ai/files/pricing-one-pager.pdf name: pricing-one-pager.pdf type: application/pdf requestId: manual-reply-20260320-002 responses: '200': description: Inbox message sent successfully content: application/json: schema: type: object properties: status: type: string enum: - success message: type: string data: type: object properties: contactId: type: number description: Contact ID conversationId: type: number description: Conversation used for the manual reply type: type: string enum: - EMAIL - LINKEDIN description: Channel that was used for the reply success: type: boolean description: >- Whether the message dispatch was accepted by the worker message: type: string description: Worker response message required: - contactId - conversationId - type - success - message required: - status - message - data examples: default: summary: Manual reply accepted by the worker value: status: success message: Inbox message sent successfully data: contactId: 123 conversationId: 456 type: EMAIL success: true message: Message queued successfully '400': description: Invalid payload or the message service was unavailable '404': description: Contact, sender identity, or matching conversation not found security: - apiKey: [] components: securitySchemes: apiKey: type: apiKey in: header name: x-api-key ````