diff --git a/action/index.cjs b/action/index.cjs
index a37bbd11..896311dc 100644
--- a/action/index.cjs
+++ b/action/index.cjs
@@ -150469,18 +150469,20 @@ const robot = (app) => {
         const includePatterns = (process.env.INCLUDE_PATTERNS || '').split(',').filter((v) => Boolean(v.trim()));
         loglevel_1.default.debug('ignoreList:', ignoreList);
         loglevel_1.default.debug('ignorePatterns:', ignorePatterns);
+        loglevel_1.default.debug('includePatterns:', includePatterns);
         changedFiles = changedFiles?.filter((file) => {
             const url = new URL(file.contents_url);
+            const pathname = decodeURIComponent(url.pathname);
             // if includePatterns is not empty, only include files that match the pattern
             if (includePatterns.length) {
-                return matchPatterns(includePatterns, url.pathname);
+                return matchPatterns(includePatterns, pathname);
             }
             if (ignoreList.includes(file.filename)) {
                 return false;
             }
             // if ignorePatterns is not empty, ignore files that match the pattern
             if (ignorePatterns.length) {
-                return !matchPatterns(ignorePatterns, url.pathname);
+                return !matchPatterns(ignorePatterns, pathname);
             }
             return true;
         });
@@ -150502,10 +150504,10 @@ const robot = (app) => {
             }
             try {
                 const res = await chat?.codeReview(patch);
-                if (!!res) {
+                if (!res.lgtm && !!res.review_comment) {
                     ress.push({
                         path: file.filename,
-                        body: res,
+                        body: res.review_comment,
                         position: patch.split('\n').length - 1,
                     });
                 }
@@ -150519,7 +150521,7 @@ const robot = (app) => {
                 repo: repo.repo,
                 owner: repo.owner,
                 pull_number: context.pullRequest().pull_number,
-                body: "Code review by ChatGPT",
+                body: ress.length ? "Code review by ChatGPT" : "LGTM 👍",
                 event: 'COMMENT',
                 commit_id: commits[commits.length - 1].sha,
                 comments: ress,
@@ -150588,15 +150590,23 @@ class Chat {
         const answerLanguage = process.env.LANGUAGE
             ? `Answer me in ${process.env.LANGUAGE},`
             : '';
-        const prompt = process.env.PROMPT ||
-            'Below is a code patch, please help me do a brief code review on it. Any bug risks and/or improvement suggestions are welcome:';
-        return `${prompt}, ${answerLanguage}:
-  ${patch}
+        const userPrompt = process.env.PROMPT || 'Please review the following code patch. Focus on potential bugs, risks, and improvement suggestions.';
+        const jsonFormatRequirement = '\nProvide your feedback in a strict JSON format with the following structure:\n' +
+            '{\n' +
+            '  "lgtm": boolean, // true if the code looks good to merge, false if there are concerns\n' +
+            '  "review_comment": string // Your detailed review comments. You can use markdown syntax in this string, but the overall response must be a valid JSON\n' +
+            '}\n' +
+            'Ensure your response is a valid JSON object.\n';
+        return `${userPrompt}${jsonFormatRequirement} ${answerLanguage}:
+    ${patch}
     `;
     };
     codeReview = async (patch) => {
         if (!patch) {
-            return '';
+            return {
+                lgtm: true,
+                review_comment: ""
+            };
         }
         console.time('code-review cost');
         const prompt = this.generatePrompt(patch);
@@ -150611,12 +150621,27 @@ class Chat {
             temperature: +(process.env.temperature || 0) || 1,
             top_p: +(process.env.top_p || 0) || 1,
             max_tokens: process.env.max_tokens ? +process.env.max_tokens : undefined,
+            response_format: {
+                type: "json_object"
+            },
         });
         console.timeEnd('code-review cost');
         if (res.choices.length) {
-            return res.choices[0].message.content;
+            try {
+                const json = JSON.parse(res.choices[0].message.content || "");
+                return json;
+            }
+            catch (e) {
+                return {
+                    lgtm: false,
+                    review_comment: res.choices[0].message.content || ""
+                };
+            }
         }
-        return '';
+        return {
+            lgtm: true,
+            review_comment: ""
+        };
     };
 }
 exports.Chat = Chat;
diff --git a/action/src/chat.d.ts b/action/src/chat.d.ts
index 88fd6b1f..00c54cd9 100644
--- a/action/src/chat.d.ts
+++ b/action/src/chat.d.ts
@@ -3,5 +3,8 @@ export declare class Chat {
     private isAzure;
     constructor(apikey: string);
     private generatePrompt;
-    codeReview: (patch: string) => Promise<string | null>;
+    codeReview: (patch: string) => Promise<{
+        lgtm: boolean;
+        review_comment: string;
+    }>;
 }
diff --git a/src/bot.ts b/src/bot.ts
index dc142eec..6c1b043f 100644
--- a/src/bot.ts
+++ b/src/bot.ts
@@ -110,13 +110,15 @@ export const robot = (app: Probot) => {
 
       log.debug('ignoreList:', ignoreList);
       log.debug('ignorePatterns:', ignorePatterns);
+      log.debug('includePatterns:', includePatterns);
 
       changedFiles = changedFiles?.filter(
         (file) => {
           const url = new URL(file.contents_url)
+          const pathname = decodeURIComponent(url.pathname)
           // if includePatterns is not empty, only include files that match the pattern
           if (includePatterns.length) {
-            return matchPatterns(includePatterns, url.pathname)
+            return matchPatterns(includePatterns, pathname)
           }
 
           if (ignoreList.includes(file.filename)) {
@@ -125,7 +127,7 @@ export const robot = (app: Probot) => {
 
           // if ignorePatterns is not empty, ignore files that match the pattern
           if (ignorePatterns.length) {
-            return !matchPatterns(ignorePatterns, url.pathname)
+            return !matchPatterns(ignorePatterns, pathname)
           }
 
           return true
@@ -156,10 +158,10 @@ export const robot = (app: Probot) => {
         }
         try {
           const res = await chat?.codeReview(patch);
-          if (!!res) {
+          if (!res.lgtm && !!res.review_comment) {
             ress.push({
               path: file.filename,
-              body: res,
+              body: res.review_comment,
               position: patch.split('\n').length - 1,
             })
           }
@@ -172,7 +174,7 @@ export const robot = (app: Probot) => {
           repo: repo.repo,
           owner: repo.owner,
           pull_number: context.pullRequest().pull_number,
-          body: "Code review by ChatGPT",
+          body: ress.length ? "Code review by ChatGPT" : "LGTM 👍",
           event: 'COMMENT',
           commit_id: commits[commits.length - 1].sha,
           comments: ress,
diff --git a/src/chat.ts b/src/chat.ts
index b6a547b2..bb82e536 100644
--- a/src/chat.ts
+++ b/src/chat.ts
@@ -31,18 +31,26 @@ export class Chat {
         ? `Answer me in ${process.env.LANGUAGE},`
         : '';
 
-    const prompt =
-        process.env.PROMPT ||
-        'Below is a code patch, please help me do a brief code review on it. Any bug risks and/or improvement suggestions are welcome:';
+    const userPrompt = process.env.PROMPT || 'Please review the following code patch. Focus on potential bugs, risks, and improvement suggestions.';
+    
+    const jsonFormatRequirement = '\nProvide your feedback in a strict JSON format with the following structure:\n' +
+        '{\n' +
+        '  "lgtm": boolean, // true if the code looks good to merge, false if there are concerns\n' +
+        '  "review_comment": string // Your detailed review comments. You can use markdown syntax in this string, but the overall response must be a valid JSON\n' +
+        '}\n' +
+        'Ensure your response is a valid JSON object.\n';
 
-    return `${prompt}, ${answerLanguage}:
-  ${patch}
+    return `${userPrompt}${jsonFormatRequirement} ${answerLanguage}:
+    ${patch}
     `;
   };
 
-  public codeReview = async (patch: string) => {
+  public codeReview = async (patch: string): Promise<{ lgtm: boolean, review_comment: string }> => {
     if (!patch) {
-      return '';
+      return {
+        lgtm: true,
+        review_comment: ""
+      };
     }
 
     console.time('code-review cost');
@@ -59,14 +67,28 @@ export class Chat {
       temperature: +(process.env.temperature || 0) || 1,
       top_p: +(process.env.top_p || 0) || 1,
       max_tokens: process.env.max_tokens ? +process.env.max_tokens : undefined,
+      response_format: {
+        type: "json_object"
+      },
     });
 
     console.timeEnd('code-review cost');
 
     if (res.choices.length) {
-      return res.choices[0].message.content;
+      try {
+        const json = JSON.parse(res.choices[0].message.content || "");
+        return json
+      } catch (e) {
+        return {
+          lgtm: false,
+          review_comment: res.choices[0].message.content || ""
+        }
+      }
     }
 
-    return '';
+    return {
+      lgtm: true,
+      review_comment: ""
+    }
   };
 }