curl https://ai-gateway.helicone.ai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_HELICONE_API_KEY" \
  -d '{
    "model": "gpt-4o-mini/openai",
    "messages": [
      {
        "role": "user",
        "content": "Hello, how are you?"
      }
    ]
  }'