diff --git a/apps/server/src/routes/github/routes/list-comments.ts b/apps/server/src/routes/github/routes/list-comments.ts
index 1813923e..2c057709 100644
--- a/apps/server/src/routes/github/routes/list-comments.ts
+++ b/apps/server/src/routes/github/routes/list-comments.ts
@@ -43,6 +43,16 @@ interface GraphQLResponse {
   errors?: Array<{ message: string }>;
 }
 
+/** Timeout for GitHub API requests in milliseconds */
+const GITHUB_API_TIMEOUT_MS = 30000;
+
+/**
+ * Validate cursor format (GraphQL cursors are typically base64 strings)
+ */
+function isValidCursor(cursor: string): boolean {
+  return /^[A-Za-z0-9+/=]+$/.test(cursor);
+}
+
 /**
  * Fetch comments for a specific issue using GitHub GraphQL API
  */
@@ -53,33 +63,45 @@ async function fetchIssueComments(
   issueNumber: number,
   cursor?: string
 ): Promise<IssueCommentsResult> {
-  const cursorParam = cursor ? `, after: "${cursor}"` : '';
+  // Validate cursor format to prevent potential injection
+  if (cursor && !isValidCursor(cursor)) {
+    throw new Error('Invalid cursor format');
+  }
 
-  const query = `{
-    repository(owner: "${owner}", name: "${repo}") {
-      issue(number: ${issueNumber}) {
-        comments(first: 50${cursorParam}) {
-          totalCount
-          pageInfo {
-            hasNextPage
-            endCursor
-          }
-          nodes {
-            id
-            author {
-              login
-              avatarUrl
+  // Use GraphQL variables instead of string interpolation for safety
+  const query = `
+    query GetIssueComments($owner: String!, $repo: String!, $issueNumber: Int!, $cursor: String) {
+      repository(owner: $owner, name: $repo) {
+        issue(number: $issueNumber) {
+          comments(first: 50, after: $cursor) {
+            totalCount
+            pageInfo {
+              hasNextPage
+              endCursor
+            }
+            nodes {
+              id
+              author {
+                login
+                avatarUrl
+              }
+              body
+              createdAt
+              updatedAt
             }
-            body
-            createdAt
-            updatedAt
           }
         }
       }
-    }
-  }`;
+    }`;
 
-  const requestBody = JSON.stringify({ query });
+  const variables = {
+    owner,
+    repo,
+    issueNumber,
+    cursor: cursor || null,
+  };
+
+  const requestBody = JSON.stringify({ query, variables });
 
   const response = await new Promise<GraphQLResponse>((resolve, reject) => {
     const gh = spawn('gh', ['api', 'graphql', '--input', '-'], {
@@ -87,12 +109,19 @@ async function fetchIssueComments(
       env: execEnv,
     });
 
+    // Add timeout to prevent hanging indefinitely
+    const timeoutId = setTimeout(() => {
+      gh.kill();
+      reject(new Error('GitHub API request timed out'));
+    }, GITHUB_API_TIMEOUT_MS);
+
     let stdout = '';
     let stderr = '';
     gh.stdout.on('data', (data: Buffer) => (stdout += data.toString()));
     gh.stderr.on('data', (data: Buffer) => (stderr += data.toString()));
 
     gh.on('close', (code) => {
+      clearTimeout(timeoutId);
       if (code !== 0) {
         return reject(new Error(`gh process exited with code ${code}: ${stderr}`));
       }
diff --git a/apps/server/src/routes/github/routes/validate-issue.ts b/apps/server/src/routes/github/routes/validate-issue.ts
index d7c9ffc0..8d51c4b1 100644
--- a/apps/server/src/routes/github/routes/validate-issue.ts
+++ b/apps/server/src/routes/github/routes/validate-issue.ts
@@ -21,6 +21,8 @@ import {
   issueValidationSchema,
   ISSUE_VALIDATION_SYSTEM_PROMPT,
   buildValidationPrompt,
+  ValidationComment,
+  ValidationLinkedPR,
 } from './validation-schema.js';
 import {
   trySetValidationRunning,
@@ -35,24 +37,6 @@ import { getAutoLoadClaudeMdSetting } from '../../../lib/settings-helpers.js';
 /** Valid model values for validation */
 const VALID_MODELS: readonly AgentModel[] = ['opus', 'sonnet', 'haiku'] as const;
 
-/**
- * Comment structure for validation prompt
- */
-interface ValidationComment {
-  author: string;
-  createdAt: string;
-  body: string;
-}
-
-/**
- * Linked PR structure for validation prompt
- */
-interface ValidationLinkedPR {
-  number: number;
-  title: string;
-  state: string;
-}
-
 /**
  * Request body for issue validation
  */
diff --git a/apps/server/src/routes/github/routes/validation-schema.ts b/apps/server/src/routes/github/routes/validation-schema.ts
index e33a2bda..010fcd7f 100644
--- a/apps/server/src/routes/github/routes/validation-schema.ts
+++ b/apps/server/src/routes/github/routes/validation-schema.ts
@@ -155,7 +155,7 @@ Be thorough in your analysis but focus on files that are directly relevant to th
 /**
  * Comment data structure for validation prompt
  */
-interface ValidationComment {
+export interface ValidationComment {
   author: string;
   createdAt: string;
   body: string;
@@ -164,7 +164,7 @@ interface ValidationComment {
 /**
  * Linked PR data structure for validation prompt
  */
-interface ValidationLinkedPR {
+export interface ValidationLinkedPR {
   number: number;
   title: string;
   state: string;
@@ -207,7 +207,9 @@ export function buildValidationPrompt(
     // Limit to most recent 10 comments to control prompt size
     const recentComments = comments.slice(-10);
     const commentsText = recentComments
-      .map((c) => `**${c.author}** (${new Date(c.createdAt).toLocaleDateString()}):\n${c.body}`)
+      .map(
+        (c) => `**${c.author}** (${new Date(c.createdAt).toISOString().slice(0, 10)}):\n${c.body}`
+      )
       .join('\n\n---\n\n');
 
     commentsSection = `\n\n### Comments (${comments.length} total${comments.length > 10 ? ', showing last 10' : ''})\n\n${commentsText}`;
diff --git a/apps/ui/src/components/views/github-issues-view/hooks/use-issue-comments.ts b/apps/ui/src/components/views/github-issues-view/hooks/use-issue-comments.ts
index e0505b36..b5b3534f 100644
--- a/apps/ui/src/components/views/github-issues-view/hooks/use-issue-comments.ts
+++ b/apps/ui/src/components/views/github-issues-view/hooks/use-issue-comments.ts
@@ -101,6 +101,7 @@ export function useIssueComments(issueNumber: number | null): UseIssueCommentsRe
       setHasNextPage(false);
       setEndCursor(undefined);
       setLoading(false);
+      setError(null);
     }
 
     return () => {