OpenAI

OpenAI: GPT-5.1-Codex

GPT-5.1-Codex is a specialized version of GPT-5.1 optimized for software engineering and coding workflows. It is designed for both interactive development sessions and long, independent execution of complex engineering tasks....

textvisioncode

Specifications

Context Window400K
Modalitiestext, vision, code
Statusavailable
Categorythird-party
Model IDopenai/gpt-5.1-codex

Quick Start

TypeScript
import OpenAI from 'openai'

const client = new OpenAI({
  apiKey: process.env.HANZO_API_KEY,
  baseURL: 'https://api.hanzo.ai/v1'
})

const response = await client.chat.completions.create({
  model: 'openai/gpt-5.1-codex',
  messages: [{ role: 'user', content: 'Hello!' }]
})

console.log(response.choices[0].message.content)
Python
from openai import OpenAI

client = OpenAI(
    api_key=os.environ["HANZO_API_KEY"],
    base_url="https://api.hanzo.ai/v1"
)

response = client.chat.completions.create(
    model="openai/gpt-5.1-codex",
    messages=[{"role": "user", "content": "Hello!"}]
)

print(response.choices[0].message.content)
cURL
curl https://api.hanzo.ai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $HANZO_API_KEY" \
  -d '{
    "model": "openai/gpt-5.1-codex",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'
Go
package main

import (
    "context"
    "fmt"
    "os"

    "github.com/sashabaranov/go-openai"
)

func main() {
    cfg := openai.DefaultConfig(os.Getenv("HANZO_API_KEY"))
    cfg.BaseURL = "https://api.hanzo.ai/v1"
    client := openai.NewClientWithConfig(cfg)

    resp, _ := client.CreateChatCompletion(context.Background(),
        openai.ChatCompletionRequest{
            Model: "openai/gpt-5.1-codex",
            Messages: []openai.ChatCompletionMessage{
                {Role: openai.ChatMessageRoleUser, Content: "Hello!"},
            },
        },
    )
    fmt.Println(resp.Choices[0].Message.Content)
}

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