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gpt-oss-120b

Text Generation • OpenAI
@cf/openai/gpt-oss-120b

OpenAI’s open-weight models designed for powerful reasoning, agentic tasks, and versatile developer use cases – gpt-oss-120b is for production, general purpose, high reasoning use-cases.

Model Info
Context Window ↗128,000 tokens
Unit Pricing$0.35 per M input tokens, $0.75 per M output tokens

Playground

Try out this model with Workers AI LLM Playground. It does not require any setup or authentication and an instant way to preview and test a model directly in the browser.

Launch the LLM Playground

Usage

Worker - Streaming

 
export interface Env {
  AI: Ai;
}


export default {
  async fetch(request, env): Promise<Response> {


    const messages = [
      { role: "system", content: "You are a friendly assistant" },
      {
        role: "user",
        content: "What is the origin of the phrase Hello, World",
      },
    ];


    const stream = await env.AI.run("@cf/openai/gpt-oss-120b", {
      messages,
      stream: true,
    });


    return new Response(stream, {
      headers: { "content-type": "text/event-stream" },
    });
  },
} satisfies ExportedHandler<Env>;

Worker

 
export interface Env {
  AI: Ai;
}


export default {
  async fetch(request, env): Promise<Response> {


    const messages = [
      { role: "system", content: "You are a friendly assistant" },
      {
        role: "user",
        content: "What is the origin of the phrase Hello, World",
      },
    ];
    const response = await env.AI.run("@cf/openai/gpt-oss-120b", { messages });


    return Response.json(response);
  },
} satisfies ExportedHandler<Env>;

Python

 
import os
import requests


ACCOUNT_ID = "your-account-id"
AUTH_TOKEN = os.environ.get("CLOUDFLARE_AUTH_TOKEN")


prompt = "Tell me all about PEP-8"
response = requests.post(
  f"https://api.cloudflare.com/client/v4/accounts/{ACCOUNT_ID}/ai/run/@cf/openai/gpt-oss-120b",
    headers={"Authorization": f"Bearer {AUTH_TOKEN}"},
    json={
      "messages": [
        {"role": "system", "content": "You are a friendly assistant"},
        {"role": "user", "content": prompt}
      ]
    }
)
result = response.json()
print(result)

curl
Terminal window
curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run/@cf/openai/gpt-oss-120b \
  -X POST \
  -H "Authorization: Bearer $CLOUDFLARE_AUTH_TOKEN" \
  -d '{ "messages": [{ "role": "system", "content": "You are a friendly assistant" }, { "role": "user", "content": "Why is pizza so good" }]}'

Parameters

* indicates a required field

Input

  • input one of required

    • 0 string

    • 1 array

      • items object

        • role string

          The role of the message input. One of user, assistant, system, or developer.

        • content one of

          • 0 string

            The content of the message as a string.

          • 1 array

            Refer to OpenAI Responses API docs to learn more about supported content types.

            • items object

Output

  • 0 object

  • 1 string

API Schemas

The following schemas are based on JSON Schema

{
    "type": "object",
    "title": "GPT_OSS_Responses",
    "properties": {
        "input": {
            "oneOf": [
                {
                    "type": "string"
                },
                {
                    "type": "array",
                    "items": {
                        "type": "object",
                        "properties": {
                            "role": {
                                "type": "string",
                                "description": "The role of the message input. One of user, assistant, system, or developer.",
                                "enum": [
                                    "user",
                                    "assistant",
                                    "system",
                                    "developer"
                                ]
                            },
                            "content": {
                                "oneOf": [
                                    {
                                        "type": "string",
                                        "description": "The content of the message as a string."
                                    },
                                    {
                                        "type": "array",
                                        "description": "Refer to OpenAI Responses API docs to learn more about supported content types.",
                                        "items": {
                                            "type": "object",
                                            "properties": {}
                                        }
                                    }
                                ]
                            }
                        }
                    }
                }
            ]
        }
    },
    "required": [
        "input"
    ]
}