OpenAI API vs Anthropic API Comparison

// OpenAI API — product analysis with structured output
import OpenAI from 'openai';
import { z } from 'zod';

const client = new OpenAI({ apiKey: process.env.OPENAI_API_KEY });

const ProductSchema = z.object({
  name: z.string(),
  category: z.string(),
  sentiment: z.enum(['positive', 'negative', 'neutral']),
  keyFeatures: z.array(z.string()),
  score: z.number().min(1).max(10)
});

const response = await client.beta.chat.completions.parse({
  model: 'gpt-5-2026-02',
  messages: [
    { role: 'system', content: 'Review and analyze the product.' },
    { role: 'user', content: 'iPhone 16 Pro Max review: ...' }
  ],
  response_format: { type: 'json_schema', json_schema: { /* zod schema */ } }
});

const product = ProductSchema.parse(response.choices[0].message.parsed);

// Anthropic API — document analysis and structured output
import Anthropic from '@anthropic-ai/sdk';

const client = new Anthropic({ apiKey: process.env.ANTHROPIC_API_KEY });

// Long document analysis (1M token context - Opus 4.7)
const message = await client.messages.create({
  model: 'claude-opus-4-7',
  max_tokens: 4096,
  system: 'Analyze legal documents and identify risks.',
  messages: [
    {
      role: 'user',
      content: [
        { type: 'text', text: 'Assess the risk in this contract:' },
        { type: 'text', text: contractText } // 100k+ token document
      ]
    }
  ]
});

// Tool use (function calling)
const withTools = await client.messages.create({
  model: 'claude-opus-4-7',
  max_tokens: 1024,
  tools: [{ name: 'get_weather', input_schema: { /* ... */ } }],
  messages: [{ role: 'user', content: 'What is the weather in Istanbul?' }]
});