diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
index 472f6b6..52eca53 100644
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -1,13 +1,13 @@
 # CODEOWNERS - Automatically assigns reviewers based on file paths
 
 # Default owner for everything
-* @codex
+* @groupthinking
 
 # Frontend
-*.tsx @Vercel
-*.jsx @Vercel
-*.css @Vercel
-/frontend/ @Vercel
+*.tsx @groupthinking
+*.jsx @groupthinking
+*.css @groupthinking
+/frontend/ @groupthinking
 
 # Backend
 *.py @groupthinking
@@ -16,11 +16,11 @@
 /api/ @groupthinking
 
 # Infrastructure
-/.github/ @Claude
-*.yml @Claude
-*.yaml @Claude
-Dockerfile @Claude
+/.github/ @groupthinking
+*.yml @groupthinking
+*.yaml @groupthinking
+Dockerfile @groupthinking
 
 # Documentation
-*.md @Copilot
-/docs/ @Copilot
+*.md @groupthinking
+/docs/ @groupthinking
diff --git a/.github/workflows/auto-label.yml b/.github/workflows/auto-label.yml
index f0934ef..3f4ea69 100644
--- a/.github/workflows/auto-label.yml
+++ b/.github/workflows/auto-label.yml
@@ -2,6 +2,11 @@ name: Auto Label
 on:
   pull_request:
     types: [opened, reopened, synchronized]
+
+permissions:
+  contents: read
+  pull-requests: write
+
 jobs:
   label:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/issue-triage.yml b/.github/workflows/issue-triage.yml
index c8649bf..15134f8 100644
--- a/.github/workflows/issue-triage.yml
+++ b/.github/workflows/issue-triage.yml
@@ -2,6 +2,10 @@ name: Issue Triage
 on:
   issues:
     types: [opened]
+
+permissions:
+  issues: write
+
 jobs:
   triage:
     runs-on: ubuntu-latest
@@ -22,12 +26,23 @@ jobs:
             labels.push('needs-triage');
 
             if (labels.length > 0) {
-              await github.rest.issues.addLabels({
+              // Fetch existing labels to avoid "Label does not exist" errors
+              const { data: repoLabels } = await github.rest.issues.listLabelsForRepo({
                 owner: context.repo.owner,
                 repo: context.repo.repo,
-                issue_number: issue.number,
-                labels: labels
+                per_page: 100,
               });
+              const existingLabelNames = new Set(repoLabels.map(l => l.name));
+              const labelsToAdd = labels.filter(l => existingLabelNames.has(l));
+
+              if (labelsToAdd.length > 0) {
+                await github.rest.issues.addLabels({
+                  owner: context.repo.owner,
+                  repo: context.repo.repo,
+                  issue_number: issue.number,
+                  labels: labelsToAdd
+                });
+              }
             }
 
             await github.rest.issues.createComment({
diff --git a/.github/workflows/pr-checks.yml b/.github/workflows/pr-checks.yml
index 00f340a..22ed3c2 100644
--- a/.github/workflows/pr-checks.yml
+++ b/.github/workflows/pr-checks.yml
@@ -2,6 +2,11 @@ name: PR Checks
 on:
   pull_request:
     types: [opened, reopened, synchronize, edited]
+
+permissions:
+  contents: read
+  pull-requests: write
+
 jobs:
   validate:
     runs-on: ubuntu-latest
diff --git a/src/index.ts b/src/index.ts
index c29abb7..a12c45d 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -8,6 +8,10 @@ import { AutonomousAgent } from './services/agent.js';
 import { XMCPServer } from './mcp/server.js';
 
 async function main() {
+  // Redirect console.log to stderr so it doesn't conflict with
+  // MCP StdioServerTransport which uses stdout for protocol messages
+  console.log = (...args: unknown[]) => console.error(...args);
+
   console.log('═══════════════════════════════════════════════════');
   console.log('  MyXstack - Autonomous AI Agent on X (Twitter)');
   console.log('═══════════════════════════════════════════════════\n');
diff --git a/src/services/agent.ts b/src/services/agent.ts
index 326fb38..e48bbb0 100644
--- a/src/services/agent.ts
+++ b/src/services/agent.ts
@@ -11,6 +11,7 @@ export class AutonomousAgent {
   private grokService: GrokService;
   private config: AgentConfig;
   private processedMentions: Set<string> = new Set();
+  private static readonly MAX_PROCESSED_MENTIONS = 10000;
   private isRunning: boolean = false;
   private pollingIntervalId: NodeJS.Timeout | null = null;
   private isProcessing: boolean = false;
@@ -90,10 +91,19 @@ export class AutonomousAgent {
 
       console.log(`\n📬 [${new Date().toLocaleTimeString()}] Found ${newMentions.length} new mention(s)!\n`);
 
-      // Process each mention
-      for (const mention of newMentions) {
-        await this.processMention(mention);
-        this.processedMentions.add(mention.post.id);
+      // Process mentions oldest-first (API returns newest first) to maintain
+      // chronological insertion order in the Set for proper pruning behavior
+      for (let i = newMentions.length - 1; i >= 0; i--) {
+        await this.processMention(newMentions[i]);
+        this.processedMentions.add(newMentions[i].post.id);
+      }
+
+      // Prune oldest entries (from beginning of Set) to prevent unbounded memory growth
+      // Sets maintain insertion order, so slice(0, excess) removes oldest entries
+      if (this.processedMentions.size > AutonomousAgent.MAX_PROCESSED_MENTIONS) {
+        const excess = this.processedMentions.size - AutonomousAgent.MAX_PROCESSED_MENTIONS;
+        const toDelete = Array.from(this.processedMentions).slice(0, excess);
+        toDelete.forEach(id => this.processedMentions.delete(id));
       }
     } catch (error) {
       console.error('❌ Error in processing loop:', error);
diff --git a/src/services/grok.ts b/src/services/grok.ts
index d71ffdc..60d50f2 100644
--- a/src/services/grok.ts
+++ b/src/services/grok.ts
@@ -4,6 +4,14 @@
  */
 import { XThread, GrokAnalysis, AgentAction } from '../types/index.js';
 
+interface GrokApiResponse {
+  choices: Array<{
+    message?: {
+      content?: string;
+    };
+  }>;
+}
+
 export class GrokService {
   private apiKey: string;
   private simulationMode: boolean = false;
@@ -59,7 +67,7 @@ export class GrokService {
         throw new Error(`Grok API error: ${response.status}`);
       }
 
-      const data: any = await response.json();
+      const data = await response.json() as GrokApiResponse;
       const analysisText = data.choices[0]?.message?.content || '';
       
       // Use the mention post ID so replies target the specific post where the agent was mentioned
diff --git a/src/services/xapi.ts b/src/services/xapi.ts
index f80be1e..0044205 100644
--- a/src/services/xapi.ts
+++ b/src/services/xapi.ts
@@ -6,6 +6,7 @@ import { XPost, XThread, Mention, XAPIConfig } from '../types/index.js';
 
 export class XAPIClient {
   private config: XAPIConfig;
+  // Track the most recent mention ID to enable pagination (avoid re-fetching)
   private lastMentionId: string | null = null;
   private simulationMode: boolean = false;
 
@@ -44,17 +45,31 @@ 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)');
         return [];
       }
 
-      return this.parseMentions(mentionsResponse.data);
+      const mentions = this.parseMentions(mentionsResponse.data);
+
+      // Track the newest mention ID for pagination on the next poll
+      if (mentionsResponse.data.length > 0 && typeof mentionsResponse.data[0].id === 'string') {
+        this.lastMentionId = mentionsResponse.data[0].id;
+      }
+
+      return mentions;
     } catch (error) {
       console.error('Error fetching mentions:', error);
       return [];
@@ -77,7 +92,17 @@ export class XAPIClient {
         'GET'
       );
 
-      return this.parseThread(response.data || []);
+      if (!response || !response.data) {
+        console.warn('Invalid response from X API (thread)');
+        return null;
+      }
+
+      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;
@@ -181,10 +206,10 @@ export class XAPIClient {
     };
   }
 
-  private parseThread(tweets: { created_at: string; [key: string]: 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) => 
+    const sorted = [...tweets].sort((a, b) =>
       new Date(a.created_at).getTime() - new Date(b.created_at).getTime()
     );