{
    "action": "tool_call",
    "reasoning": "I need to understand the treatment arms in the adsl table to show adverse event variation across them. The ae table has adverse events but no treatment arm column visible in the first 30 columns. I need to check if ae has treatment arm info, or if I need to join through USUBJID. Let me first see what treatment arms exist in adsl.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT ACTARMCD, ACTARM, COUNT(*) as subject_count FROM raw.adsl WHERE ACTARMCD IS NOT NULL GROUP BY ACTARMCD, ACTARM ORDER BY subject_count DESC",
        "purpose": "Get treatment arm breakdown to understand the primary category for safety analysis",
        "source": "raw"
    }
}