Claude Sonnet 4

curl https://api.anthropic.com/v1/messages \
  -H "Content-Type: application/json" \
  -H "x-api-key: $ANTHROPIC_API_KEY" \
  -H "anthropic-version: 2023-06-01" \
  -d '{
    "model": "claude-sonnet-4",
    "max_tokens": 1024,
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

# pip install anthropic
from anthropic import Anthropic

client = Anthropic()  # reads ANTHROPIC_API_KEY from env

resp = client.messages.create(
    model="claude-sonnet-4",
    max_tokens=1024,
    messages=[{"role": "user", "content": "Hello!"}],
)
print(resp.content[0].text)

// npm install @anthropic-ai/sdk
import Anthropic from "@anthropic-ai/sdk";

const client = new Anthropic();  // reads ANTHROPIC_API_KEY from env

const resp = await client.messages.create({
  model: "claude-sonnet-4",
  max_tokens: 1024,
  messages: [{ role: "user", content: "Hello!" }],
});
console.log(resp.content[0].text);