OpenAI Chat Completions Reasoning with AI Gateway

import OpenAI from 'openai';
 
const apiKey = process.env.AI_GATEWAY_API_KEY || process.env.VERCEL_OIDC_TOKEN;
 
const openai = new OpenAI({
  apiKey,
  baseURL: 'https://ai-gateway.vercel.sh/v1',
});
 
const completion = await openai.chat.completions.create({
  model: 'openai/gpt-6-astra',
  messages: [
    {
      role: 'user',
      content: 'What is the meaning of life? Think before answering.',
    },
  ],
  stream: false,
  // AI Gateway extension fields are not included in the upstream SDK types.
  ...{
    reasoning: {
      effort: 'medium',
    },
  },
});
 
const message = completion.choices[0].message;
console.log(
  'Reasoning:',
  'reasoning' in message ? message.reasoning : undefined,
);
console.log('Answer:', completion.choices[0].message.content);
console.log(
  'Reasoning tokens:',
  completion.usage?.completion_tokens_details?.reasoning_tokens,
);

import os
from openai import OpenAI
 
api_key = os.getenv('AI_GATEWAY_API_KEY') or os.getenv('VERCEL_OIDC_TOKEN')
 
client = OpenAI(
    api_key=api_key,
    base_url='https://ai-gateway.vercel.sh/v1'
)
 
completion = client.chat.completions.create(
    model='openai/gpt-6-astra',
    messages=[
        {
            'role': 'user',
            'content': 'What is the meaning of life? Think before answering.'
        }
    ],
    stream=False,
    extra_body={
        'reasoning': {
            'effort': 'medium'
        }
    }
)
 
print('Reasoning:', completion.choices[0].message.reasoning)
print('Answer:', completion.choices[0].message.content)
print('Reasoning tokens:', completion.usage.completion_tokens_details.reasoning_tokens)

curl -X POST "https://ai-gateway.vercel.sh/v1/chat/completions" \
  -H "Authorization: Bearer $AI_GATEWAY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "openai/gpt-6-astra",
    "messages": [
      {
        "role": "user",
        "content": "What is the meaning of life? Think before answering."
      }
    ],
    "stream": false,
    "reasoning": {
      "effort": "medium"
    }
  }'

import OpenAI from 'openai';
 
const openai = new OpenAI({
  apiKey: process.env.AI_GATEWAY_API_KEY,
  baseURL: 'https://ai-gateway.vercel.sh/v1',
});
 
const stream = await openai.chat.completions.create({
  model: 'openai/gpt-6-astra',
  messages: [
    {
      role: 'user',
      content: 'What is the meaning of life? Think before answering.',
    },
  ],
  stream: true,
  ...{
    reasoning: {
      effort: 'medium',
    },
  },
});
 
// Reasoning and content each arrive as many small deltas, so label each
// section once rather than once per chunk.
let section: 'reasoning' | 'content' | null = null;
 
for await (const chunk of stream) {
  const delta = chunk.choices[0]?.delta;
 
  if (delta && 'reasoning' in delta && typeof delta.reasoning === 'string') {
    if (section !== 'reasoning') {
      process.stdout.write('\n[Reasoning] ');
      section = 'reasoning';
    }
    process.stdout.write(delta.reasoning);
  }
 
  if (delta?.content) {
    if (section !== 'content') {
      process.stdout.write('\n[Answer] ');
      section = 'content';
    }
    process.stdout.write(delta.content);
  }
}

import os
from openai import OpenAI
 
client = OpenAI(
    api_key=os.getenv('AI_GATEWAY_API_KEY'),
    base_url='https://ai-gateway.vercel.sh/v1'
)
 
stream = client.chat.completions.create(
    model='openai/gpt-6-astra',
    messages=[
        {
            'role': 'user',
            'content': 'What is the meaning of life? Think before answering.'
        }
    ],
    stream=True,
    extra_body={
        'reasoning': {
            'effort': 'medium'
        }
    }
)
 
# Reasoning and content each arrive as many small deltas, so label each
# section once rather than once per chunk.
section = None
 
for chunk in stream:
    if chunk.choices and chunk.choices[0].delta:
        delta = chunk.choices[0].delta
 
        if getattr(delta, 'reasoning', None):
            if section != 'reasoning':
                print('\n[Reasoning] ', end='', flush=True)
                section = 'reasoning'
            print(delta.reasoning, end='', flush=True)
 
        if getattr(delta, 'content', None):
            if section != 'content':
                print('\n[Answer] ', end='', flush=True)
                section = 'content'
            print(delta.content, end='', flush=True)

curl -X POST "https://ai-gateway.vercel.sh/v1/chat/completions" \
  -H "Authorization: Bearer $AI_GATEWAY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "openai/gpt-6-astra",
    "messages": [
      {
        "role": "user",
        "content": "What is the meaning of life? Think before answering."
      }
    ],
    "stream": true,
    "reasoning": {
      "effort": "medium"
    }
  }'