curl "https://api.rotavision.com/v1/sankalp/usage?start_date=2026-01-01&group_by=model" \
  -H "Authorization: Bearer rv_live_..."

{
  "period": {
    "start": "2026-01-01T00:00:00Z",
    "end": "2026-02-01T10:30:00Z"
  },
  "summary": {
    "total_requests": 125430,
    "total_tokens": {
      "input": 45678900,
      "output": 23456780,
      "total": 69135680
    },
    "total_cost": {
      "usd": 234.56,
      "inr": 19540.23
    },
    "avg_latency_ms": 1250
  },
  "breakdown": [
    {
      "model": "gpt-5-mini",
      "provider": "openai",
      "requests": 45000,
      "tokens": {
        "input": 18000000,
        "output": 9000000,
        "total": 27000000
      },
      "cost": {
        "usd": 108.00,
        "inr": 9000.00
      },
      "avg_latency_ms": 1100
    },
    {
      "model": "sarvam-large",
      "provider": "sarvam",
      "requests": 52000,
      "tokens": {
        "input": 15678900,
        "output": 8456780,
        "total": 24135680
      },
      "cost": {
        "usd": 48.27,
        "inr": 4022.50
      },
      "avg_latency_ms": 890
    },
    {
      "model": "claude-4.5-sonnet",
      "provider": "anthropic",
      "requests": 28430,
      "tokens": {
        "input": 12000000,
        "output": 6000000,
        "total": 18000000
      },
      "cost": {
        "usd": 78.29,
        "inr": 6524.17
      },
      "avg_latency_ms": 1650
    }
  ],
  "daily_trend": [
    {
      "date": "2026-01-31",
      "requests": 4521,
      "cost": {"usd": 8.42, "inr": 701.67}
    },
    {
      "date": "2026-02-01",
      "requests": 2341,
      "cost": {"usd": 4.21, "inr": 350.83}
    }
  ]
}