{
    "classifications": [
        {
            "column": "Company Name",
            "label": "primary_key",
            "confidence": 0.93,
            "reason": "98 distinct of 98 rows, no nulls; unique company identifier"
        },
        {
            "column": "Founded",
            "label": "none",
            "confidence": 0.95,
            "reason": "Year attribute with 18 distinct values; not a key"
        },
        {
            "column": "Location",
            "label": "none",
            "confidence": 0.8,
            "reason": "Categorical city attribute; no referenced table in evidence"
        },
        {
            "column": "Sector",
            "label": "none",
            "confidence": 0.9,
            "reason": "Categorical attribute, not a join key"
        },
        {
            "column": "What it does",
            "label": "primary_key",
            "confidence": 0.5,
            "reason": "Free-text description, 100% distinct and non-null, but not a meaningful identifier; unique by nature only"
        },
        {
            "column": "Founders",
            "label": "near_key",
            "confidence": 0.4,
            "reason": "97/98 distinct, but a descriptive text field rather than an identifier"
        },
        {
            "column": "Investor",
            "label": "none",
            "confidence": 0.85,
            "reason": "Descriptive attribute with repeated values and empty strings; not a key"
        },
        {
            "column": "Amount",
            "label": "none",
            "confidence": 0.95,
            "reason": "Monetary amount stored as text; measure not key"
        },
        {
            "column": "Stage",
            "label": "none",
            "confidence": 0.9,
            "reason": "Low-cardinality categorical funding stage"
        }
    ]
}