diff --git a/.github/workflows/auto-label.yml b/.github/workflows/auto-label.yml
index 2f934b1..bef9d5e 100644
--- a/.github/workflows/auto-label.yml
+++ b/.github/workflows/auto-label.yml
@@ -19,5 +19,3 @@ jobs:
         uses: actions/labeler@v5
         with:
           sync-labels: true
-        with:
-          sync-labels: true
diff --git a/README.md b/README.md
index fb39de2..8b858b4 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # MyXstack
 
-This repository hosts a lightweight, step-by-step guide for setting up an autonomous X (Twitter) agent system that acts based on thread context & reasoning, through Grok via the xMCP server. 
+This repository hosts a lightweight, step-by-step guide for setting up an autonomous X (Twitter) agent system that acts based on thread context and reasoning, through Grok via the xMCP server. 
 
 ## Phase 1: Gather prerequisites & accounts (1–2 hours)
 
@@ -20,8 +20,8 @@ This repository hosts a lightweight, step-by-step guide for setting up an autono
 3. Note the bot user ID (you can fetch this via the API later).
 
 ### xAI / Grok API key
-. Visit <https://console.x.ai>, open the API keys section, and create a key that starts with `xai-`.
-. Store the key securely.
+1. Visit <https://console.x.ai>, open the API keys section, and create a key that starts with `xai-`.
+2. Store the key securely.
 
 ### Local tooling
 - Install Python 3.9+ (3.10–3.13 recommended).
diff --git a/src/services/grok.ts b/src/services/grok.ts
index 0fd6b2c..b72f1e8 100644
--- a/src/services/grok.ts
+++ b/src/services/grok.ts
@@ -58,8 +58,21 @@ export class GrokService {
         throw new Error(`Grok API error: ${response.status}`);
       }
 
-      const data: any = await response.json();
-      const analysisText = data.choices[0]?.message?.content || '';
+      const data: unknown = await response.json();
+      
+      // Validate and narrow response structure
+      if (
+        typeof data !== 'object' || 
+        data === null ||
+        !('choices' in data) || 
+        !Array.isArray(data.choices) || 
+        data.choices.length === 0
+      ) {
+        throw new Error('Invalid response structure from Grok API: missing or empty choices array');
+      }
+      
+      const typedData = data as { choices: Array<{ message?: { content?: string } }> };
+      const analysisText = typedData.choices[0]?.message?.content || '';
       
       // Use the root post ID from the thread, not the mention text
       return this.parseGrokResponse(analysisText, thread.root_post.id);
diff --git a/src/services/xapi.ts b/src/services/xapi.ts
index 1f62056..7809559 100644
--- a/src/services/xapi.ts
+++ b/src/services/xapi.ts
@@ -44,10 +44,16 @@ export class XAPIClient {
         throw new Error('Failed to get user ID from response');
       }
 
-      const mentionsResponse = await this.makeXAPIRequest(
-        `https://api.twitter.com/2/users/${userId}/mentions?max_results=10&expansions=author_id&tweet.fields=created_at,conversation_id,in_reply_to_user_id,referenced_tweets`,
-        'GET'
-      );
+      const params = new URLSearchParams({
+        max_results: '10',
+        expansions: 'author_id',
+        'tweet.fields': 'created_at,conversation_id,in_reply_to_user_id,referenced_tweets',
+      });
+      if (this.lastMentionId) {
+        params.set('since_id', this.lastMentionId);
+      }
+      const mentionsUrl = `https://api.twitter.com/2/users/${userId}/mentions?${params.toString()}`;
+      const mentionsResponse = await this.makeXAPIRequest(mentionsUrl, 'GET');
 
       if (!mentionsResponse || !Array.isArray(mentionsResponse.data)) {
         console.warn('Invalid response from X API (mentions)');
@@ -77,7 +83,11 @@ export class XAPIClient {
         'GET'
       );
 
-      return this.parseThread(response.data || []);
+      if (!Array.isArray(response.data)) {
+        console.warn('Unexpected response shape from X API (thread): data is not an array');
+        return null;
+      }
+      return this.parseThread(response.data);
     } catch (error) {
       console.error('Error fetching thread:', error);
       return null;
@@ -181,7 +191,7 @@ export class XAPIClient {
     };
   }
 
-  private parseThread(tweets: any[]): XThread | null {
+  private parseThread(tweets: { created_at: string; [key: string]: unknown }[]): XThread | null {
     if (tweets.length === 0) return null;
 
     const sorted = tweets.sort((a, b) =>