# Reply to a conversation

Adds a reply to an existing conversation. Supports both contact (customer/lead) and admin replies.

### Path Parameters

- id - The conversation ID (short ID)

### Request Body

The request body varies based on who is sending the reply:

#### Contact Reply (customer/lead)

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| type | string | Yes | Must be "contact" |
| userId | string | No* | External user ID from your system |
| id | string | No* | Featurebase contact ID (24-character ObjectId) |
| bodyMarkdown | string | Yes | The message content in markdown format. Images referenced by URL or as base64 data URIs will be automatically uploaded and stored. |
| messageType | string | Yes | Must be "reply" |

*At least one of userId or id is required.

#### Admin Reply

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| type | string | Yes | Must be "admin" |
| id | string | Yes | Featurebase admin ID (24-character ObjectId) |
| bodyMarkdown | string | Yes | The message content in markdown format. Images referenced by URL or as base64 data URIs will be automatically uploaded and stored. |
| messageType | string | Yes | "reply" for customer-visible reply, "note" for internal note |

### Response

Returns the created conversation part object with a 201 Created status. The response includes both bodyHtml (with signed image URLs) and bodyMarkdown fields.

### Example Contact Reply

json
{
  "type": "contact",
  "userId": "user_123",
  "bodyMarkdown": "Thank you for your help!",
  "messageType": "reply"
}


### Example Admin Reply

json
{
  "type": "admin",
  "id": "507f1f77bcf86cd799439011",
  "bodyMarkdown": "I'm happy to help! Here's what you need to do...",
  "messageType": "reply"
}


### Example Admin Note (Internal)

json
{
  "type": "admin",
  "id": "507f1f77bcf86cd799439011",
  "bodyMarkdown": "Customer seems frustrated, escalating to tier 2.",
  "messageType": "note"
}


### Example Response

json
{
  "object": "conversation_part",
  "id": "3",
  "partType": "user_msg",
  "bodyHtml": "Thank you for your help!",
  "bodyMarkdown": "Thank you for your help!",
  "author": {
    "type": "customer",
    "id": "676f0f6765bdaa7d7d760f88",
    "name": "John Doe",
    "email": "john@example.com"
  },
  "channel": "desktop",
  "createdAt": "2025-01-15T10:40:00.000Z",
  "updatedAt": "2025-01-15T10:40:00.000Z"
}


### Version Availability

This endpoint is only available in API version 2026-01-01.nova and newer.

Endpoint: POST /v2/conversations/{id}/reply
Version: 2026-01-01.nova
Security: bearerAuth

## Header parameters:

  - `Featurebase-Version` (string)
    API version for this request. Defaults to your organization's configured API version if not specified.
    Example: "2026-01-01.nova"

## Path parameters:

  - `id` (string, required)
    Conversation ID (short ID)
    Example: "12345"

## Response 400 fields (application/json):

  - `error` (object, required)

  - `error.type` (string, required)
    The type of error returned
    Enum: "invalid_request_error"

  - `error.code` (string, required)
    Machine-readable error code
    Enum: "invalid_content", "missing_parameter", "invalid_parameter", "invalid_request"

  - `error.message` (string, required)
    Human-readable error message
    Example: "An error occurred"

  - `error.param` (string)
    The parameter that caused the error (if applicable)
    Example: "id"

  - `error.status` (number, required)
    HTTP status code
    Enum: 400

## Response 404 fields (application/json):

  - `error` (object, required)

  - `error.type` (string, required)
    The type of error returned
    Enum: "invalid_request_error"

  - `error.code` (string, required)
    Machine-readable error code
    Enum: "conversation_not_found", "contact_not_found", "admin_not_found"

  - `error.message` (string, required)
    Human-readable error message
    Example: "An error occurred"

  - `error.param` (string)
    The parameter that caused the error (if applicable)
    Example: "id"

  - `error.status` (number, required)
    HTTP status code
    Enum: 404