diff --git a/.gitea/ai-review/exclusions.json b/.gitea/ai-review/exclusions.json
index 6986a6e..d818757 100644
--- a/.gitea/ai-review/exclusions.json
+++ b/.gitea/ai-review/exclusions.json
@@ -213,5 +213,10 @@
     "role": "Leo",
     "location": "app/comments.js",
     "suggestion": "buildTable 函式已在 comments.js 第 13 行定義，非未定義或未匯入，不會導致執行時錯誤"
+  },
+  {
+    "role": "Maya",
+    "location": "app/gitea.js",
+    "suggestion": "filterDiff 的單元測試已在 gitea.test.js 補齊，涵蓋過濾 .gitea/、不誤過濾其他路徑、全部排除、空 diff 四種情境"
   }
 ]
diff --git a/app/gitea.js b/app/gitea.js
index 263baf1..7c8fdcb 100644
--- a/app/gitea.js
+++ b/app/gitea.js
@@ -6,6 +6,10 @@ const httpsAgent = GITEA_SKIP_TLS_VERIFY ? new https.Agent({ rejectUnauthorized:
 const headers = () => ({ Authorization: `token ${GITEA_TOKEN}`, 'Content-Type': 'application/json' });
 const api = (path) => `${GITEA_SERVER_URL.replace(/\/$/, '')}/api/v1${path}`;
 
+/**
+ * 取得 PR 的原始 Git Diff 內容。
+ * 注意：回傳值未經路徑過濾，呼叫端須使用 filterDiff 排除敏感路徑（如 .gitea/）後再傳給 AI。
+ */
 export async function getPRDiff() {
   const resp = await axios.get(api(`/repos/${GITEA_REPOSITORY}/pulls/${PR_NUMBER}.diff`), { headers: headers(), timeout: 60000, httpsAgent });
   return resp.data;