curl -X GET https://api.thinnest.ai/sessions/{session_id}/messages \
  -H "Authorization: Bearer $THINNESTAI_API_KEY"

{
  "session_id": "sess_customer_001",
  "messages": [
    {
      "role": "user",
      "content": "What are your business hours?",
      "timestamp": "2026-03-07T12:00:00Z"
    },
    {
      "role": "assistant",
      "content": "Our business hours are Monday through Friday, 9 AM to 6 PM EST.",
      "timestamp": "2026-03-07T12:00:01Z",
      "usage": {
        "input_tokens": 45,
        "output_tokens": 22
      }
    },
    {
      "role": "user",
      "content": "Are you open on weekends?",
      "timestamp": "2026-03-07T12:01:15Z"
    },
    {
      "role": "assistant",
      "content": "Yes, we're open on Saturdays from 10 AM to 2 PM. Closed on Sundays.",
      "timestamp": "2026-03-07T12:01:16Z",
      "usage": {
        "input_tokens": 78,
        "output_tokens": 20
      }
    }
  ]
}