diff --git a/api.py b/api.py
index 43e26dc..1e912b4 100644
--- a/api.py
+++ b/api.py
@@ -12,6 +12,7 @@ API 层 (api)
 """
 
 import hashlib
+from pathlib import Path
 
 from fastapi import FastAPI, Request
 from fastapi.responses import JSONResponse
@@ -39,7 +40,7 @@ storage = Storage(tasks, STORAGE_ROOT)
 app = FastAPI(title="7z-encrypt 服务端")
 
 
-def _sha256(path) -> str:
+def _sha256(path: str | Path) -> str:
     h = hashlib.sha256()
     with open(path, "rb") as f:
         for chunk in iter(lambda: f.read(1 << 20), b""):