OpenAI

GPT-4o, GPT-4, GPT-3.5 Turbo

The most popular LLM provider. Access GPT-4o, GPT-4 Turbo, and GPT-3.5 models.

Setup

1. Install Packages

npm install @yourgpt/copilot-sdk @yourgpt/llm-sdk openai

2. Get API Key

Get your API key from platform.openai.com

3. Add Environment Variable

.env.local

OPENAI_API_KEY=sk-...

4. Usage

import { generateText } from '@yourgpt/llm-sdk';
import { openai } from '@yourgpt/llm-sdk/openai';

const result = await generateText({
  model: openai('gpt-4o'),
  prompt: 'Explain quantum computing simply.',
});

console.log(result.text);

5. Streaming (API Route)

app/api/chat/route.ts

import { streamText } from '@yourgpt/llm-sdk';
import { openai } from '@yourgpt/llm-sdk/openai';

export async function POST(req: Request) {
  const { messages } = await req.json();

  const result = await streamText({
    model: openai('gpt-4o'),
    system: 'You are a helpful assistant.',
    messages,
  });

  return result.toTextStreamResponse();
}

Available Models

// Latest and best
openai('gpt-4o')              // Fastest GPT-4 class
openai('gpt-5.2')         // Cost-effective, very capable

// GPT-4 Turbo
openai('gpt-4-turbo')         // 128K context

// GPT-3.5
openai('gpt-3.5-turbo')       // Fast and cheap

Configuration Options

import { openai } from '@yourgpt/llm-sdk/openai';

// Custom API key
const model = openai('gpt-4o', {
  apiKey: 'sk-custom-key',
});

// With generation options
const result = await generateText({
  model: openai('gpt-4o'),
  prompt: 'Hello',
  temperature: 0.7,        // 0-2, default 1
  maxTokens: 4096,         // Max response length
});

Tool Calling

OpenAI has excellent tool/function calling support:

import { generateText, tool } from '@yourgpt/llm-sdk';
import { openai } from '@yourgpt/llm-sdk/openai';
import { z } from 'zod';

const result = await generateText({
  model: openai('gpt-4o'),
  prompt: 'What is the weather in Tokyo?',
  tools: {
    getWeather: tool({
      description: 'Get weather for a city',
      parameters: z.object({
        city: z.string().describe('City name'),
      }),
      execute: async ({ city }) => {
        // Your weather API call
        return { temperature: 22, condition: 'sunny' };
      },
    }),
  },
  maxSteps: 5, // Allow multiple tool calls
});

Vision (Image Input)

GPT-4o supports image analysis. Send images in your messages:

const result = await generateText({
  model: openai('gpt-4o'),
  messages: [
    {
      role: 'user',
      content: [
        { type: 'text', text: "What's in this image?" },
        { type: 'image', image: base64ImageData },
      ],
    },
  ],
});

With Copilot UI

Use with the Copilot React components:

app/providers.tsx

'use client';

import { CopilotProvider } from '@yourgpt/copilot-sdk/react';

export function Providers({ children }: { children: React.ReactNode }) {
  return (
    <CopilotProvider runtimeUrl="/api/chat">
      {children}
    </CopilotProvider>
  );
}

MCP servers + Reasoning effort (Responses API)

Setting mcpServers or reasoningEffort on a request routes the call through OpenAI's /v1/responses endpoint instead of Chat Completions (those fields aren't accepted on Chat Completions).

const result = await runtime.response({
  prompt: 'Create a GitHub issue with the latest deploy errors.',
  mcpServers: [{
    label: 'github',
    url: 'https://mcp.github.com/sse',
    headers: { Authorization: `Bearer ${process.env.GH_TOKEN}` },
    allowedTools: ['create_issue'],
    requireApproval: 'never',
  }],
  reasoningEffort: 'high',
});

Maps to:

tools: [{ type: 'mcp', server_label, server_url, headers, allowed_tools, require_approval }]
reasoning: { effort: 'high', summary: 'auto' }
store: false (one-shot semantics — no persistence on OpenAI's side)
text.format when responseFormat is also set

reasoningEffort accepts minimal/low/medium/high directly. Use { raw: { effort: 'xhigh' } } to pass the wider native range (none/xhigh) for o-series and gpt-5 reasoning models.

See Structured Output → MCP servers and → Reasoning effort for the cross-provider reference.

Pricing

Model	Input	Output
gpt-4o	$2.50/1M tokens	$10/1M tokens
gpt-5.2	$0.15/1M tokens	$0.60/1M tokens
gpt-3.5-turbo	$0.50/1M tokens	$1.50/1M tokens

Prices as of late 2024. Check OpenAI pricing for current rates.

Next Steps

Anthropic - Try Claude models
generateText() - Full API reference
tool() - Define tools with Zod

OpenAI

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