{
    "action": "tool_call",
    "reasoning": "No evidence has been gathered yet, so the earlier prose claims about heavy users are unverified. I'll compute outcome averages by daily-usage bucket over the full table to test that pattern.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT CASE WHEN Daily_Usage_Hours < 3 THEN '1) <3h' WHEN Daily_Usage_Hours < 5 THEN '2) 3-5h' WHEN Daily_Usage_Hours < 7 THEN '3) 5-7h' WHEN Daily_Usage_Hours < 9 THEN '4) 7-9h' ELSE '5) 9h+' END AS usage_bucket, COUNT(*) AS students, ROUND(AVG(Sleep_Duration_Hours),2) AS avg_sleep_hours, ROUND(AVG(Sleep_Quality_Score),2) AS avg_sleep_quality, ROUND(AVG(Perceived_Stress_Score),2) AS avg_stress, ROUND(AVG(Mental_Health_Index),2) AS avg_mental_health, ROUND(AVG(Academic_Performance_GPA),2) AS avg_gpa FROM raw.Social_media_impact_on_life GROUP BY 1 ORDER BY 1",
        "purpose": "Verify whether heavier daily social media use is associated with worse sleep, stress, mental health and GPA across all 4,500 students",
        "source": "raw"
    }
}