diff --git a/gmail-sentiment-analysis/Cards.gs b/gmail-sentiment-analysis/Cards.gs
index 6a07c735d..f0360318d 100644
--- a/gmail-sentiment-analysis/Cards.gs
+++ b/gmail-sentiment-analysis/Cards.gs
@@ -16,28 +16,24 @@ limitations under the License.
 
 
 /**
- * Builds the card for to display in the sidepanel of gmail.
+ * Builds the card to display in the sidepanel of gmail.
  * @return {CardService.Card} The card to show to the user.
  */
 
 function buildCard_GmailHome(notifyOk = false) {
-  const imageUrl = 'https://icons.iconarchive.com/icons/roundicons/100-free-solid/48/spy-icon.png';
-  const image = CardService.newImage()
-    .setImageUrl(imageUrl);
+  const imageUrl = 'https://fonts.gstatic.com/s/i/googlematerialicons/dynamic_feed/v6/black-24dp/1x/gm_dynamic_feed_black_24dp.png';
 
   const cardHeader = CardService.newCardHeader()
     .setImageUrl(imageUrl)
     .setImageStyle(CardService.ImageStyle.CIRCLE)
     .setTitle("Analyze your GMail");
 
-  const action = CardService.newAction()
-    .setFunctionName('analyzeSentiment');
+  const action = CardService.newAction().setFunctionName('analyzeSentiment');
   const button = CardService.newTextButton()
     .setText('Identify angry customers')
     .setOnClickAction(action)
     .setTextButtonStyle(CardService.TextButtonStyle.FILLED);
-  const buttonSet = CardService.newButtonSet()
-    .addButton(button);
+  const buttonSet = CardService.newButtonSet().addButton(button);
 
   const section = CardService.newCardSection()
     .setHeader("Emails sentiment analysis")
@@ -51,9 +47,8 @@ function buildCard_GmailHome(notifyOk = false) {
    * This builds the card that contains the footer that informs
    * the user about the successful execution of the Add-on.
    */
-
   if (notifyOk == true) {
-    let fixedFooter = CardService.newFixedFooter()
+    const fixedFooter = CardService.newFixedFooter()
       .setPrimaryButton(
         CardService.newTextButton()
           .setText("Analysis complete")
diff --git a/gmail-sentiment-analysis/Gmail.gs b/gmail-sentiment-analysis/Gmail.gs
index 7e4b3c621..d4e6fe2b2 100644
--- a/gmail-sentiment-analysis/Gmail.gs
+++ b/gmail-sentiment-analysis/Gmail.gs
@@ -20,30 +20,46 @@ limitations under the License.
  */
 
 function analyzeSentiment() {
-  emailSentiment();
+  analyzeAndLabelEmailSentiment();
   return buildCard_GmailHome(true);
 }
 
 /**
- * Gets the last 10 threads in the inbox and the corresponding messages.
- * Fetches the label that should be applied to negative messages.
- * The processSentiment is called on each message 
- * and tested with RegExp to check for a negative answer from the model
+ * Analyzes the sentiment of recent emails in the inbox and labels threads with
+ * negative sentiment as "UPSET TONE 😡".
  */
+function analyzeAndLabelEmailSentiment() {
+  const labelName = "UPSET TONE 😡";
+  const maxThreads = 10;
 
-function emailSentiment() {
-  const threads = GmailApp.getInboxThreads(0, 10);
-  const msgs = GmailApp.getMessagesForThreads(threads);
-  const label_upset = GmailApp.getUserLabelByName("UPSET TONE 😡");
-  let currentPrediction;
-
-  for (let i = 0; i < msgs.length; i++) {
-    for (let j = 0; j < msgs[i].length; j++) {
-      let emailText = msgs[i][j].getPlainBody();
-      currentPrediction = processSentiment(emailText);
-      if (currentPrediction === true) {
-        label_upset.addToThread(msgs[i][j].getThread());
+  // Get the label, or create it if it doesn't exist.
+  const label = GmailApp.getUserLabelByName(labelName) || GmailApp.createLabel(labelName);
+
+  // Get the first 'maxThreads' threads from the inbox.
+  const threads = GmailApp.getInboxThreads(0, maxThreads);
+
+  // Process each thread.
+  for (const thread of threads) {
+    const messages = thread.getMessages();
+
+    // Process each message within the thread.
+    for (const message of messages) {
+      const emailText = message.getPlainBody();
+      const isUpset = isNegativeSentiment(emailText);
+
+      if (isUpset) {
+        label.addToThread(thread);
       }
     }
   }
 }
+
+/**
+ * Determines if the given text has a negative sentiment.
+ * 
+ * @param {string} text - The text to analyze.
+ * @returns {boolean} True if the sentiment is negative, false otherwise.
+ */
+function isNegativeSentiment(text) {
+  return processSentiment(text) === 'negative';
+}
diff --git a/gmail-sentiment-analysis/Vertex.gs b/gmail-sentiment-analysis/Vertex.gs
index 25d1994a3..3f02fefff 100644
--- a/gmail-sentiment-analysis/Vertex.gs
+++ b/gmail-sentiment-analysis/Vertex.gs
@@ -15,7 +15,7 @@ limitations under the License.
 */
 
 const PROJECT_ID = '[ADD YOUR GCP PROJECT ID HERE]';
-const VERTEX_AI_LOCATION = 'europe-west2';
+const VERTEX_AI_LOCATION = 'us-central1';
 const MODEL_ID = 'gemini-1.5-pro-002';
 
 /**
@@ -28,11 +28,7 @@ const MODEL_ID = 'gemini-1.5-pro-002';
  */
 
 function processSentiment(emailText) {
-  const prompt = `
-  Analyze the following message: ${emailText}.
-  If the sentiment of this message is negative, answer with FALSE.
-  If the sentiment of this message is neutral or positive, answer with TRUE.
-  Do not use any other words than the ones requested in this prompt as a response!`;
+  const prompt = `Analyze the sentiment of the following message: ${emailText}`;
 
   const request = {
     "contents": [{
@@ -44,6 +40,20 @@ function processSentiment(emailText) {
     "generationConfig": {
       "temperature": 0.9,
       "maxOutputTokens": 1024,
+      "responseMimeType": "application/json",
+      "responseSchema": {
+        "type": "object",
+        "properties": {
+          "response": {
+            "type": "string",
+            "enum": [
+              "positive",
+              "negative",
+              "neutral",
+            ]
+          }
+        }
+      }
     }
   };
 
@@ -62,8 +72,7 @@ function processSentiment(emailText) {
 
   const response = UrlFetchApp.fetch(url, fetchOptions);
   const payload = JSON.parse(response.getContentText());
+  const text = JSON.parse(payload.candidates[0].content.parts[0].text);
 
-  const regex = /FALSE/;
-
-  return regex.test(payload.candidates[0].content.parts[0].text);
+  return text.response;
 }
diff --git a/gmail-sentiment-analysis/appsscript.json b/gmail-sentiment-analysis/appsscript.json
index cf6273f63..9b2be96ac 100644
--- a/gmail-sentiment-analysis/appsscript.json
+++ b/gmail-sentiment-analysis/appsscript.json
@@ -5,14 +5,13 @@
     "https://www.googleapis.com/auth/cloud-platform",
     "https://www.googleapis.com/auth/script.locale",
     "https://www.googleapis.com/auth/gmail.addons.execute",
-    "https://mail.google.com/",
     "https://www.googleapis.com/auth/gmail.labels",
     "https://www.googleapis.com/auth/gmail.modify"
   ],
   "addOns": {
     "common": {
       "name": "Productivity toolbox",
-      "logoUrl": "https://icons.iconarchive.com/icons/roundicons/100-free-solid/64/spy-icon.png",
+      "logoUrl": "https://fonts.gstatic.com/s/i/googlematerialicons/dynamic_feed/v6/black-24dp/1x/gm_dynamic_feed_black_24dp.png",
       "useLocaleFromApp": true
     },
     "gmail": {