{
    "action": "tool_call",
    "reasoning": "No evidence is available in this turn, so the numbers in my earlier draft are unverified. I'll recompute the per-surface ace, double-fault, rank and sample-size figures in one query over raw.raw_kaggle. TRY_CAST guards against text-typed columns.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT Surface, COUNT(*) AS player_matches, COUNT(TRY_CAST(Aces AS DOUBLE)) AS rows_with_serve_stats, ROUND(AVG(TRY_CAST(Aces AS DOUBLE)),2) AS avg_aces, ROUND(AVG(TRY_CAST(DFs AS DOUBLE)),2) AS avg_dfs, ROUND(AVG(TRY_CAST(Rk AS DOUBLE)),0) AS avg_rank, ROUND(MEDIAN(TRY_CAST(Rk AS DOUBLE)),0) AS median_rank FROM raw.raw_kaggle GROUP BY Surface ORDER BY avg_aces DESC",
        "purpose": "Verify per-surface average aces, double faults, rank and sample size",
        "source": "raw"
    }
}