diff --git a/app/harness/batching.py b/app/harness/batching.py
index 5e24d3e..6385839 100644
--- a/app/harness/batching.py
+++ b/app/harness/batching.py
@@ -139,9 +139,7 @@ def _select_mixed_by_task_type(
         n_correct = round(len(errs) * correct_ratio / (1 - correct_ratio))
         available = correct_by_type.get(task_type, [])
         sampled = (
-            list(available)
-            if len(available) <= n_correct
-            else rng.sample(available, n_correct)
+            list(available) if len(available) <= n_correct else rng.sample(available, n_correct)
         )
         grouped[task_type] = errs + sampled
 
diff --git a/app/harness/log.py b/app/harness/log.py
index 8d9f970..d2f54fd 100644
--- a/app/harness/log.py
+++ b/app/harness/log.py
@@ -68,9 +68,7 @@ class HarnessLog:
         self._conn.execute("PRAGMA journal_mode=WAL")
         self._init_fixed_tables()
         resolved_sha = git_sha or _get_git_sha()
-        config_json = (
-            json.dumps(config_snapshot, ensure_ascii=False) if config_snapshot else None
-        )
+        config_json = json.dumps(config_snapshot, ensure_ascii=False) if config_snapshot else None
         self._conn.execute(
             "INSERT OR IGNORE INTO _runs"
             " (run_id, git_sha, started_at, config, status)"
@@ -143,18 +141,14 @@ class HarnessLog:
         col_names = ", ".join(cols)
         values = [enriched[c] for c in cols]
         if mode == "upsert":
-            sql = (
-                f"INSERT OR REPLACE INTO {table} ({col_names}) VALUES ({placeholders})"
-            )
+            sql = f"INSERT OR REPLACE INTO {table} ({col_names}) VALUES ({placeholders})"
         else:
             sql = f"INSERT INTO {table} ({col_names}) VALUES ({placeholders})"
         with self._lock:
             self._conn.execute(sql, values)
             self._conn.commit()
 
-    def insert_many(
-        self, table: str, records: list[dict[str, Any]], mode: str = "append"
-    ) -> None:
+    def insert_many(self, table: str, records: list[dict[str, Any]], mode: str = "append") -> None:
         """批量插入多条记录。
 
         参数:
@@ -192,9 +186,7 @@ class HarnessLog:
         with self._lock:
             cursor = self._conn.execute(sql, params)
             columns = [desc[0] for desc in cursor.description]
-            return [
-                dict(zip(columns, row, strict=True)) for row in cursor.fetchall()
-            ]
+            return [dict(zip(columns, row, strict=True)) for row in cursor.fetchall()]
 
     def log_event(self, event_type: str, payload: dict[str, Any]) -> None:
         """向 _events 表写入一条事件。
@@ -205,8 +197,7 @@ class HarnessLog:
         """
         with self._lock:
             self._conn.execute(
-                "INSERT INTO _events (run_id, timestamp, event_type, payload)"
-                " VALUES (?, ?, ?, ?)",
+                "INSERT INTO _events (run_id, timestamp, event_type, payload) VALUES (?, ?, ?, ?)",
                 (
                     self._run_id,
                     _now_iso(),
@@ -280,15 +271,10 @@ def _read_table(
 
         if question_ids is not None:
             placeholders = ", ".join(["?"] * len(question_ids))
-            sql = (
-                f"SELECT * FROM {table}"
-                f" WHERE run_id = ? AND question_id IN ({placeholders})"
-            )
+            sql = f"SELECT * FROM {table} WHERE run_id = ? AND question_id IN ({placeholders})"
             rows = conn.execute(sql, (run_id, *question_ids)).fetchall()
         else:
-            rows = conn.execute(
-                f"SELECT * FROM {table} WHERE run_id = ?", (run_id,)
-            ).fetchall()
+            rows = conn.execute(f"SELECT * FROM {table} WHERE run_id = ?", (run_id,)).fetchall()
 
         return [dict(r) for r in rows]
     finally: