{
    "action": "tool_call",
    "reasoning": "No evidence is available in this turn, so I will re-ground the column-type answer with one profile query: exact row and distinct-user counts, plus distinct counts for the categorical columns and ranges for the numeric ones.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT COUNT(*) AS n_rows, COUNT(DISTINCT user_id) AS distinct_users, COUNT(DISTINCT gender) AS gender_d, COUNT(DISTINCT occupation_type) AS occupation_d, COUNT(DISTINCT chronotype) AS chronotype_d, COUNT(DISTINCT primary_bedtime_app) AS app_d, COUNT(DISTINCT sleep_debt_category) AS debt_cat_d, COUNT(DISTINCT blue_light_filter_active) AS blue_d, MIN(age) AS age_min, MAX(age) AS age_max, MIN(bedtime_phone_minutes) AS phone_min, MAX(bedtime_phone_minutes) AS phone_max, MIN(total_sleep_hours) AS sleep_min, MAX(total_sleep_hours) AS sleep_max, MIN(next_day_fatigue_score) AS fatigue_min, MAX(next_day_fatigue_score) AS fatigue_max, MIN(_ingestion_timestamp) AS ingest_min, MAX(_ingestion_timestamp) AS ingest_max FROM raw.bedtime_screentime_sleep_debt",
        "purpose": "Verify exact counts of identifier, categorical dimensions, numeric ranges and the only timestamp (ingestion)",
        "source": "raw"
    }
}