diff --git a/app/comments.js b/app/comments.js
index 779a177..a8f2198 100644
--- a/app/comments.js
+++ b/app/comments.js
@@ -63,7 +63,7 @@ export async function postNewCriticalComments(findings) {
     return;
   }
   for (const f of criticals) {
-    const body = `## 🚨 嚴重問題\n\n| 審查員 | 位置 | 建議 |\n|--------|------|------|\n| ${f.role} | ${f.location} | ${f.suggestion} |`;
+    const body = `## 🚨 嚴重問題\n\n${buildTable([f])}`;
     await postComment(body);
     console.log(`  ✅ 嚴重問題 comment 發布: [${f.role}] ${f.location}`);
   }
diff --git a/app/findings.js b/app/findings.js
index f381cfa..8a6a5cb 100644
--- a/app/findings.js
+++ b/app/findings.js
@@ -11,7 +11,6 @@ const LEVELS = ['critical', 'warning', 'info'];
 export async function analyzeWithRole(role, diff) {
   console.log(`  [${role.name}] 開始分析...`);
   const findings = await chatJSON(role.system_prompt, `以下是 Git Diff 內容：\n\n${diff}`);
-  // 確保每筆都有必要欄位，並標記為新問題
   const valid = findings.filter(f => f.level && f.role && f.location && f.suggestion)
     .map(f => ({ ...f, is_new: true }));
   console.log(`  [${role.name}] 找到 ${valid.length} 個問題`);
@@ -40,7 +39,6 @@ export function loadOldFindings(workspace) {
 
 /**
  * 合併新舊 findings，以 (role + location + suggestion前50字) 為 key 去除重複
- * 舊問題保留，新問題若與舊問題重複則捨棄
  */
 export function mergeFindings(oldFindings, newFindings) {
   const key = f => `${f.role}|${f.location}|${String(f.suggestion).slice(0, 50)}`;
@@ -63,8 +61,17 @@ export function sortByLevel(findings) {
 }
 
 /**
- * 呼叫 LLM 進行語意去重，回傳去重後的 findings
- * 失敗時降級回傳原始 findings
+ * AI 呼叫失敗時的統一降級處理
+ */
+function fallback(label, findings, e) {
+  const status = e.response?.status;
+  const reason = (status === 402 || status === 429) ? `${status} 額度/限流` : e.message;
+  console.log(`  ⚠️  ${label}失敗（${reason}），降級：保留所有問題`);
+  return findings;
+}
+
+/**
+ * 呼叫 LLM 進行語意去重，失敗時降級回傳原始 findings
  */
 export async function deduplicateWithAI(findings) {
   if (findings.length === 0) return findings;
@@ -74,29 +81,20 @@ export async function deduplicateWithAI(findings) {
 保留等級較高的版本，優先保留 critical > warning > info。
 只回傳去重後的 JSON 陣列，不要有其他文字。`;
 
-  const userContent = `以下是問題清單，請去除語意重複的項目：\n\n${JSON.stringify(findings, null, 2)}`;
-
   try {
-    const result = await chatJSON(systemPrompt, userContent);
+    const result = await chatJSON(systemPrompt, `以下是問題清單，請去除語意重複的項目：\n\n${JSON.stringify(findings, null, 2)}`);
     if (Array.isArray(result) && result.length > 0) {
       console.log(`  AI 去重: ${findings.length} -> ${result.length} 筆`);
       return result;
     }
     throw new Error('AI 回傳空陣列');
   } catch (e) {
-    const status = e.response?.status;
-    if (status === 402 || status === 429) {
-      console.log(`  ⚠️  AI 去重失敗（${status} 額度/限流），降級：保留所有問題`);
-    } else {
-      console.log(`  ⚠️  AI 去重失敗（${e.message}），降級：保留所有問題`);
-    }
-    return findings;
+    return fallback('AI 去重', findings, e);
   }
 }
 
 /**
  * 讀取排除問題檔案（從 workspace 的 EXCLUSIONS_PATH）
- * 格式：[{ role, location, suggestion }]，欄位可部分省略，省略表示萬用
  */
 export function loadExclusions(workspace) {
   const fullPath = path.join(workspace, EXCLUSIONS_PATH);
@@ -125,17 +123,14 @@ export function applyExclusions(findings, exclusions) {
   const filtered = findings.filter(f => !exclusions.some(ex => {
     const fPath = String(f.location).split(':')[0];
     const exPath = ex.location ? String(ex.location).split(':')[0] : null;
-    return (!exPath || fPath === exPath) &&
-           (!ex.role || ex.role === f.role);
+    return (!exPath || fPath === exPath) && (!ex.role || ex.role === f.role);
   }));
   console.log(`  排除過濾: ${before} -> ${filtered.length} 筆（排除 ${before - filtered.length} 筆）`);
   return filtered;
 }
 
 /**
- * 呼叫 AI 判斷哪些問題是誤報或不需處理，回傳需保留的 findings
- * exclusions 為已知誤報清單，供 AI 參考判斷
- * 失敗時降級回傳原始 findings
+ * 呼叫 AI 判斷哪些問題是誤報或不需處理，失敗時降級回傳原始 findings
  */
 export async function filterFalsePositivesWithAI(findings, exclusions = []) {
   if (findings.length === 0) return findings;
@@ -152,22 +147,14 @@ export async function filterFalsePositivesWithAI(findings, exclusions = []) {
 3. 與已知誤報清單語意相近的問題（檔案路徑相同且建議內容相似）
 只回傳需要保留的問題 JSON 陣列，不要有其他文字。${exclusionHint}`;
 
-  const userContent = `請判斷以下問題清單，移除誤報或不需處理的問題：\n\n${JSON.stringify(findings, null, 2)}`;
-
   try {
-    const result = await chatJSON(systemPrompt, userContent);
+    const result = await chatJSON(systemPrompt, `請判斷以下問題清單，移除誤報或不需處理的問題：\n\n${JSON.stringify(findings, null, 2)}`);
     if (Array.isArray(result) && result.length > 0) {
       console.log(`  AI 誤報過濾: ${findings.length} -> ${result.length} 筆`);
       return result;
     }
     throw new Error('AI 回傳空陣列或非陣列');
   } catch (e) {
-    const status = e.response?.status;
-    if (status === 402 || status === 429) {
-      console.log(`  ⚠️  AI 誤報過濾失敗（${status} 額度/限流），降級：保留所有問題`);
-    } else {
-      console.log(`  ⚠️  AI 誤報過濾失敗（${e.message}），降級：保留所有問題`);
-    }
-    return findings;
+    return fallback('AI 誤報過濾', findings, e);
   }
 }
diff --git a/app/git.js b/app/git.js
index 5006d88..b182ba0 100644
--- a/app/git.js
+++ b/app/git.js
@@ -14,20 +14,26 @@ function makeRunner(spawn) {
   };
 }
 
+function withAskpass(workspace, fn) {
+  const askpassScript = path.join(workspace, '.git-askpass.sh');
+  fs.writeFileSync(askpassScript, '#!/bin/sh\necho "$GIT_TOKEN"\n', { mode: 0o700 });
+  const credEnv = { ...process.env, GIT_ASKPASS: askpassScript, GIT_USERNAME: 'x-token', GIT_TOKEN: GITEA_TOKEN };
+  try {
+    return fn(credEnv);
+  } finally {
+    try { fs.unlinkSync(askpassScript); } catch {}
+  }
+}
+
 /**
  * Clone PR head branch to workspace/repo (idempotent)
  */
 export function cloneRepo(workspace, _spawnSync = spawnSync) {
   const run = makeRunner(_spawnSync);
-  const baseUrl = GITEA_SERVER_URL.replace(/\/$/, '');
-  const remoteUrl = `${baseUrl}/${GITEA_REPOSITORY}.git`;
+  const remoteUrl = `${GITEA_SERVER_URL.replace(/\/$/, '')}/${GITEA_REPOSITORY}.git`;
   const repoDir = path.join(workspace, 'repo');
 
-  const askpassScript = path.join(workspace, '.git-askpass.sh');
-  fs.writeFileSync(askpassScript, '#!/bin/sh\necho "$GIT_TOKEN"\n', { mode: 0o700 });
-  const credEnv = { ...process.env, GIT_ASKPASS: askpassScript, GIT_USERNAME: 'x-token', GIT_TOKEN: GITEA_TOKEN };
-
-  try {
+  return withAskpass(workspace, credEnv => {
     if (!fs.existsSync(repoDir)) {
       run(['clone', '--depth=1', '--branch', PR_HEAD_BRANCH, remoteUrl, repoDir], workspace, credEnv);
       console.log(`  ✅ repo cloned to ${repoDir}`);
@@ -36,57 +42,40 @@ export function cloneRepo(workspace, _spawnSync = spawnSync) {
       run(['checkout', PR_HEAD_BRANCH], repoDir);
       console.log(`  ✅ repo already exists, fetched latest`);
     }
-  } finally {
-    try { fs.unlinkSync(askpassScript); } catch {}
-  }
-  return repoDir;
+    return repoDir;
+  });
 }
 
 export async function commitAndPush(workspace, _spawnSync = spawnSync) {
   const run = makeRunner(_spawnSync);
-
-  const baseUrl = GITEA_SERVER_URL.replace(/\/$/, '');
-  const remoteUrl = `${baseUrl}/${GITEA_REPOSITORY}.git`;
-  const repoDir = path.join(workspace, 'repo');
-
-  // Write a temporary askpass script that reads the token from an env var,
-  // so the token value never appears in the script file itself
-  const askpassScript = path.join(workspace, '.git-askpass.sh');
-  fs.writeFileSync(askpassScript, '#!/bin/sh\necho "$GIT_TOKEN"\n', { mode: 0o700 });
-
-  const credEnv = { ...process.env, GIT_ASKPASS: askpassScript, GIT_USERNAME: 'x-token', GIT_TOKEN: GITEA_TOKEN };
+  const remoteUrl = `${GITEA_SERVER_URL.replace(/\/$/, '')}/${GITEA_REPOSITORY}.git`;
 
   try {
-    if (!fs.existsSync(repoDir)) {
-      run(['clone', '--depth=1', '--branch', PR_HEAD_BRANCH, remoteUrl, repoDir], workspace, credEnv);
-    }
+    const repoDir = cloneRepo(workspace, _spawnSync);
 
-    run(['config', 'user.email', 'ai-review[bot]@gitea'], repoDir);
-    run(['config', 'user.name', 'AI Review Bot'], repoDir);
-    run(['fetch', 'origin', PR_HEAD_BRANCH], repoDir, credEnv);
-    run(['checkout', PR_HEAD_BRANCH], repoDir);
+    await withAskpass(workspace, async credEnv => {
+      run(['config', 'user.email', 'ai-review[bot]@gitea'], repoDir);
+      run(['config', 'user.name', 'AI Review Bot'], repoDir);
 
-    // 將 findings.json 從 workspace 複製到 clone 的 repo
-    const srcFindings = path.join(workspace, FINDINGS_PATH);
-    const destFindings = path.join(repoDir, FINDINGS_PATH);
-    fs.mkdirSync(path.dirname(destFindings), { recursive: true });
-    fs.copyFileSync(srcFindings, destFindings);
+      const srcFindings = path.join(workspace, FINDINGS_PATH);
+      const destFindings = path.join(repoDir, FINDINGS_PATH);
+      fs.mkdirSync(path.dirname(destFindings), { recursive: true });
+      fs.copyFileSync(srcFindings, destFindings);
 
-    run(['add', FINDINGS_PATH], repoDir);
+      run(['add', FINDINGS_PATH], repoDir);
 
-    const status = run(['status', '--porcelain'], repoDir);
-    if (!status) {
-      console.log('  findings.json 無變更，跳過 commit');
-      return;
-    }
+      const status = run(['status', '--porcelain'], repoDir);
+      if (!status) {
+        console.log('  findings.json 無變更，跳過 commit');
+        return;
+      }
 
-    const out = run(['commit', '-m', 'chore: update ai-review findings [skip ci]'], repoDir);
-    const commitHash = out.match(/\[.+ ([a-f0-9]+)\]/)?.[1] || 'unknown';
-    run(['push', remoteUrl, PR_HEAD_BRANCH], repoDir, credEnv);
-    console.log(`  ✅ persisted findings  commit=${commitHash}  push=${PR_HEAD_BRANCH}`);
+      const out = run(['commit', '-m', 'chore: update ai-review findings [skip ci]'], repoDir);
+      const commitHash = out.match(/\[.+ ([a-f0-9]+)\]/)?.[1] || 'unknown';
+      run(['push', remoteUrl, PR_HEAD_BRANCH], repoDir, credEnv);
+      console.log(`  ✅ persisted findings  commit=${commitHash}  push=${PR_HEAD_BRANCH}`);
+    });
   } catch (e) {
     console.log(`  ⚠️  Runner failed: commit/push 失敗: ${e.message}`);
-  } finally {
-    try { fs.unlinkSync(askpassScript); } catch {}
   }
 }
diff --git a/app/gitea.js b/app/gitea.js
index 8c319b0..e35ccab 100644
--- a/app/gitea.js
+++ b/app/gitea.js
@@ -12,9 +12,8 @@ export async function getPRDiff() {
 }
 
 function filterDiff(diff, excludePrefixes) {
-  const blocks = diff.split(/(?=^diff --git )/m);
-  return blocks
-    .filter(block => !excludePrefixes.some(prefix => block.match(new RegExp(`^diff --git a/${prefix.replace(/\//g, '\\/')}`)))) 
+  return diff.split(/(?=^diff --git )/m)
+    .filter(block => !excludePrefixes.some(p => block.startsWith(`diff --git a/${p}`)))
     .join('');
 }
 
diff --git a/app/llm.js b/app/llm.js
index 4bf932f..87ace9d 100644
--- a/app/llm.js
+++ b/app/llm.js
@@ -29,12 +29,11 @@ export async function chat(systemPrompt, userContent) {
 }
 
 export async function chatJSON(systemPrompt, userContent) {
+  const text = await chat(systemPrompt, userContent);
   try {
-    let text = await chat(systemPrompt, userContent);
-    text = text.trim().replace(/^```[^\n]*\n?/, '').replace(/```$/, '').trim();
-    return JSON.parse(text);
+    return JSON.parse(text.trim().replace(/^```[^\n]*\n?/, '').replace(/```$/, '').trim());
   } catch (e) {
-    console.log(`  [LLM] 解析失敗: ${e.message}`);
+    console.log(`  [LLM] JSON 解析失敗: ${e.message}`);
     return [];
   }
 }
diff --git a/app/main.js b/app/main.js
index 67a797d..e25b839 100644
--- a/app/main.js
+++ b/app/main.js
@@ -13,7 +13,6 @@ async function main() {
   console.log(`  repo=${GITEA_REPOSITORY}  PR=#${PR_NUMBER}`);
   console.log(`  ${PR_HEAD_BRANCH} -> ${PR_BASE_BRANCH}`);
 
-  // 偵測 LLM
   const { provider, baseURL, model } = getLLMConfig();
   if (!provider) {
     console.error('❌ 未設定任何 LLM API Key，請檢查 action inputs');
@@ -21,11 +20,9 @@ async function main() {
   }
   console.log(`  LLM: provider=${provider}  model=${model}  base_url=${baseURL}`);
 
-  // 載入角色
   const roles = loadRoles();
   console.log(`  已載入 ${roles.length} 個角色: [${roles.map(r => r.name).join(', ')}]`);
 
-  // 取得 PR diff
   let diff;
   try {
     diff = await getPRDiff();
@@ -40,7 +37,6 @@ async function main() {
     process.exit(0);
   }
 
-  // 發布角色介紹 comment
   try {
     const intro = getRoleIntro(roles) + `\n\n> 🔍 服務：${provider}  模型：${model}`;
     await postComment(intro);
@@ -48,7 +44,6 @@ async function main() {
   } catch (e) {
     console.log(`  ⚠️  comment 發布失敗（繼續執行）: ${e.message}`);
   }
-  console.log('  Step1 完成');
 
   // Step2: 各角色分析 diff 產生新 findings
   console.log('\n📊 Step2: Findings 產生');
@@ -65,7 +60,6 @@ async function main() {
 
   // Step3: 讀取舊 findings，合併去重（含 AI 語意去重）
   console.log('\n🔀 Step3: Findings 合併');
-  // Clone repo 以讀取舊 findings 與排除清單
   let repoDir;
   try {
     repoDir = cloneRepo(WORKSPACE);
@@ -91,7 +85,6 @@ async function main() {
   // Step5: 寫入 findings.json，依序發布 comment
   console.log('\n📝 Step5: Findings 寫入與 Comment 發布');
   saveFindings(WORKSPACE, filtered);
-
   try {
     await postOldFindingsComment(filtered);
     await postNewNonCriticalComment(filtered);
@@ -114,7 +107,6 @@ async function main() {
     process.exit(1);
   }
   console.log('  ✅ 無嚴重問題');
-
   console.log('\n✅ Pipeline 完成');
   console.log('='.repeat(60));
 }