{
    "action": "tool_call",
    "reasoning": "No tool results are visible in evidence, so I can't cite the numbers from my earlier draft. I'll recompute the exchange segmentation from the ticker suffix in one query so the answer is grounded.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT CASE WHEN position('.' IN stock_name) > 0 THEN split_part(stock_name, '.', 2) ELSE '(no suffix)' END AS exchange_suffix, COUNT(*) AS row_count, COUNT(DISTINCT stock_name) AS tickers, COUNT(DISTINCT company_name) AS companies, MIN(date) AS first_date, MAX(date) AS last_date, MEDIAN(volume) AS median_volume, MEDIAN(close) AS median_close FROM raw.semi_conductor_se GROUP BY 1 ORDER BY row_count DESC",
        "purpose": "Segment the dataset by exchange, derived from the ticker suffix, with size, coverage and typical volume/price per segment",
        "source": "raw"
    }
}