{
    "action": "tool_call",
    "reasoning": "To list all 69 columns, their data types, and their meanings, I will query the analytics.column_overview table which contains metadata for all columns in the dataset.",
    "tool": "query_sql",
    "args": {
        "purpose": "Get all columns, types, and semantic roles for the benchmarks table",
        "source": "raw",
        "sql": "SELECT column_name, phys_type, semantic_role, rough_kind FROM analytics.column_overview WHERE table_name = 'benchmarks' ORDER BY column_name;"
    }
}