---
updatedAt: 2026-06-15T09:50:57.000Z
agentTools:
  projectIndex: https://developers.tidio.com/llms.txt
---

# Reply to a ticket

This endpoint allows you to add a reply message to an existing ticket, based on its unique ID.
This can be either a message from an operator or from a contact (user).


# OpenAPI definition

```json
{
  "openapi": "3.0.3",
  "info": {
    "title": "Tidio - Openapi",
    "version": "1.0"
  },
  "servers": [
    {
      "url": "https://api.tidio.com/"
    }
  ],
  "tags": [
    {
      "name": "Tickets"
    }
  ],
  "security": [
    {
      "ClientId": [],
      "ClientSecret": []
    }
  ],
  "paths": {
    "/tickets/{ticketId}/reply": {
      "post": {
        "tags": [
          "Tickets"
        ],
        "summary": "Reply to a ticket",
        "description": "This endpoint allows you to add a reply message to an existing ticket, based on its unique ID.\nThis can be either a message from an operator or from a contact (user).\n",
        "parameters": [
          {
            "$ref": "#/components/parameters/TicketId"
          }
        ],
        "requestBody": {
          "required": true,
          "content": {
            "application/json; version=1": {
              "schema": {
                "type": "object",
                "required": [
                  "author_type",
                  "content"
                ],
                "properties": {
                  "author_type": {
                    "type": "string",
                    "description": "Who replied",
                    "enum": [
                      "contact",
                      "operator"
                    ],
                    "example": "operator"
                  },
                  "content": {
                    "type": "string",
                    "description": "Message content"
                  },
                  "operator_id": {
                    "type": "string",
                    "format": "uuid",
                    "description": "Operator id"
                  },
                  "message_type": {
                    "type": "string",
                    "description": "Determines visibility of message",
                    "enum": [
                      "public",
                      "internal"
                    ]
                  }
                }
              },
              "examples": {
                "Reply as contact": {
                  "value": {
                    "author_type": "contact",
                    "content": "message from contact"
                  }
                },
                "Reply as operator": {
                  "value": {
                    "author_type": "operator",
                    "content": "message from operator",
                    "operator_id": "b4c3717a-d45b-4c08-ab2a-f0d38bdc0caf",
                    "message_type": "public"
                  }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "$ref": "#/components/responses/UlidResponse"
          },
          "400": {
            "$ref": "#/components/responses/BadRequestResponse"
          },
          "404": {
            "$ref": "#/components/responses/NotFoundResponse"
          },
          "422": {
            "$ref": "#/components/responses/UnprocessableEntityResponse"
          }
        }
      }
    }
  },
  "components": {
    "parameters": {
      "TicketId": {
        "in": "path",
        "name": "ticketId",
        "required": true,
        "schema": {
          "allOf": [
            {
              "$ref": "#/components/schemas/TicketID"
            }
          ]
        }
      }
    },
    "schemas": {
      "Error": {
        "type": "object",
        "properties": {
          "code": {
            "type": "string",
            "example": "bad_request",
            "title": "Error code"
          },
          "message": {
            "type": "string",
            "title": "More specific description of the error",
            "example": "The request was invalid or cannot be served. "
          }
        }
      },
      "ErrorResponse": {
        "type": "object",
        "properties": {
          "errors": {
            "type": "array",
            "items": {
              "$ref": "#/components/schemas/Error"
            }
          }
        }
      },
      "TicketID": {
        "type": "integer",
        "description": "Ticket ID",
        "example": 10000
      }
    },
    "securitySchemes": {
      "ClientId": {
        "type": "apiKey",
        "in": "header",
        "name": "X-Tidio-Openapi-Client-Id"
      },
      "ClientSecret": {
        "type": "apiKey",
        "in": "header",
        "name": "X-Tidio-Openapi-Client-Secret"
      }
    },
    "responses": {
      "BadRequestResponse": {
        "description": "Bad Request",
        "content": {
          "application/json; version=1": {
            "schema": {
              "$ref": "#/components/schemas/ErrorResponse"
            },
            "example": {
              "errors": [
                {
                  "code": "not_valid",
                  "message": "Provide at least one property to update"
                }
              ]
            }
          }
        }
      },
      "UnprocessableEntityResponse": {
        "description": "Unprocessable Entity",
        "content": {
          "application/json; version=1": {
            "schema": {
              "$ref": "#/components/schemas/ErrorResponse"
            },
            "example": {
              "errors": [
                {
                  "code": "not_valid",
                  "message": "The email must be a valid email address"
                }
              ]
            }
          }
        }
      },
      "NotFoundResponse": {
        "description": "Not Found",
        "content": {
          "application/json; version=1": {
            "schema": {
              "$ref": "#/components/schemas/ErrorResponse"
            },
            "example": {
              "errors": [
                {
                  "code": "not_found",
                  "message": "The resource cannot be found."
                }
              ]
            }
          }
        }
      },
      "UlidResponse": {
        "description": "Entity was created and their id is returned",
        "content": {
          "application/json; version=1": {
            "schema": {
              "properties": {
                "id": {
                  "type": "string",
                  "example": "01HAVMVKF90KH3EC0HK2T6QYP6"
                }
              }
            }
          }
        }
      }
    }
  }
}
```