{
    "action": "tool_call",
    "reasoning": "The prior draft cited overall correlations, but no evidence is visible to me now. I'll run the usage-band query so the threshold question has a rendered result.",
    "tool": "query_sql",
    "args": {
        "sql": "SELECT CASE WHEN Daily_Usage_Hours < 2 THEN '1: <2h' WHEN Daily_Usage_Hours < 3 THEN '2: 2-3h' WHEN Daily_Usage_Hours < 4 THEN '3: 3-4h' WHEN Daily_Usage_Hours < 5 THEN '4: 4-5h' WHEN Daily_Usage_Hours < 6 THEN '5: 5-6h' WHEN Daily_Usage_Hours < 7 THEN '6: 6-7h' WHEN Daily_Usage_Hours < 8 THEN '7: 7-8h' ELSE '8: 8h+' END AS usage_band, COUNT(*) AS students, ROUND(AVG(Mental_Health_Index),2) AS avg_mental_health, ROUND(AVG(Perceived_Stress_Score),2) AS avg_stress, ROUND(AVG(Sleep_Duration_Hours),2) AS avg_sleep_hours, ROUND(AVG(Sleep_Quality_Score),2) AS avg_sleep_quality, ROUND(AVG(Academic_Performance_GPA),3) AS avg_gpa FROM raw.Social_media_impact_on_life GROUP BY 1 ORDER BY 1",
        "purpose": "Band daily usage hours against the five outcome measures to see whether wellbeing drops sharply past a threshold or declines gradually",
        "source": "raw"
    }
}