curl -X GET "https://api.example.com/api/v1/agent_files/1/usage" \
  -H "X-API-Key: your-api-key-here"

{
  "status": {
    "code": 200,
    "message": "File usage retrieved successfully"
  },
  "data": {
    "file_id": 1,
    "file_name": "product-catalog.pdf",
    "agents": [
      {
        "id": "123",
        "name": "Customer Support Agent"
      },
      {
        "id": "456",
        "name": "Sales Agent"
      }
    ]
  }
}