{
    "dataset": str,                # Dataset identifier (required)
    "filters": dict,               # Optional filters
    "limit": int                   # Max records (default: 1000)
}

{
    "data": list[dict],            # Array of records
    "count": int,                  # Number of records
    "dataset": str                 # Dataset name
}

result = client.invoke("analytics-mcp", "fetch_data", token, {
    "dataset": "sales_2024",
    "filters": {"region": "US", "status": "completed"},
    "limit": 500
})

data = result["data"]["data"]
print(f"Fetched {result['data']['count']} records")