---
title: "Developer message"
url: "https://kongair.terwilligar.com/apis/openai-api-2-3-0/versions/ea92d048-c746-4ead-a6a8-da28d93137d1/schemas/ChatCompletionRequestDeveloperMessage"
---

> Full API specification: https://kongair.terwilligar.com/apis/openai-api-2-3-0/versions/ea92d048-c746-4ead-a6a8-da28d93137d1.md

# Developer message

Developer-provided instructions that the model should follow, regardless of messages sent by the user. With o1 models and newer, `developer` messages replace the previous `system` messages.

## OpenAPI definition

```yaml
openapi: 3.0.0
info:
  title: OpenAI API
  version: 2.3.0
servers:
  - url: https://api.openai.com/v1
components:
  schemas:
    ChatCompletionRequestMessageContentPartText:
      type: object
      title: Text content part
      description: |
        Learn about [text inputs](/docs/guides/text-generation).
      properties:
        type:
          type: string
          enum:
            - text
          description: The type of the content part.
          x-stainless-const: true
        text:
          type: string
          description: The text content.
      required:
        - type
        - text
    ChatCompletionRequestDeveloperMessage:
      type: object
      title: Developer message
      description: >
        Developer-provided instructions that the model should follow, regardless
        of

        messages sent by the user. With o1 models and newer, `developer`
        messages

        replace the previous `system` messages.
      properties:
        content:
          description: The contents of the developer message.
          oneOf:
            - type: string
              description: The contents of the developer message.
              title: Text content
            - type: array
              description: An array of content parts with a defined type. For developer
                messages, only type `text` is supported.
              title: Array of content parts
              items:
                $ref: "#/components/schemas/ChatCompletionRequestMessageContentPartText"
              minItems: 1
        role:
          type: string
          enum:
            - developer
          description: The role of the messages author, in this case `developer`.
          x-stainless-const: true
        name:
          type: string
          description: An optional name for the participant. Provides the model
            information to differentiate between participants of the same role.
      required:
        - content
        - role
```