diff --git a/crates/mem-cli/src/http_server.rs b/crates/mem-cli/src/http_server.rs
index 5f88039..dc3e743 100644
--- a/crates/mem-cli/src/http_server.rs
+++ b/crates/mem-cli/src/http_server.rs
@@ -453,7 +453,24 @@ pub async fn start_server(port: u16, api_key: String, database_url: &str) -> Res
 
 /// Health check (no auth)
 pub async fn health_check(state: web::Data<AppState>) -> HttpResponse {
+    use crate::metrics::*;
+    HEALTH_CHECKS_TOTAL.inc();
     let uptime = state.start_time.elapsed().as_secs();
+    APP_UPTIME_SECONDS.set(uptime);
+
+    // O7: Check DB dependency
+    let db_start = std::time::Instant::now();
+    match sqlx::query("SELECT 1").execute(&state.pool).await {
+        Ok(_) => {
+            DEP_DB_UP.set(1);
+            DEP_DB_LATENCY.observe(db_start.elapsed().as_secs_f64());
+        }
+        Err(_) => {
+            DEP_DB_UP.set(0);
+            HEALTH_CHECK_FAILURES.inc();
+        }
+    }
+
     HttpResponse::Ok().json(json!({"status": "ok", "uptime_seconds": uptime}))
 }