diff --git a/examples/ai-streaming/src/index.tsx b/examples/ai-streaming/src/index.tsx
index c172a666d..e8c98f0b3 100644
--- a/examples/ai-streaming/src/index.tsx
+++ b/examples/ai-streaming/src/index.tsx
@@ -40,7 +40,7 @@ class AIStreamingApp extends Widget {
         this.addChild(this._toolCall);
         this.addChild(this._streamingText);
 
-        setInterval(() => {
+        clearInterval(window.__interval); window.__interval = setInterval(() => {
             this._streamingText.tick();
         }, 50);
     }
diff --git a/examples/chat-app/src/index.tsx b/examples/chat-app/src/index.tsx
index a3a2ddb14..0d405714e 100644
--- a/examples/chat-app/src/index.tsx
+++ b/examples/chat-app/src/index.tsx
@@ -257,7 +257,7 @@ function parseBlocks(text: string): Block[] {
         }
 
         // ── Handle Paragraphs ────────────────────────
-        if (line.trim() === '') {
+        if (line.trim().length === 0) {
             blocks.push({
                 type: 'paragraph',
                 text: '',
diff --git a/packages/ui/src/prompts.ts b/packages/ui/src/prompts.ts
index b92bb28ba..b248a6ac4 100644
--- a/packages/ui/src/prompts.ts
+++ b/packages/ui/src/prompts.ts
@@ -113,7 +113,7 @@ async function promptSelect<T = string>(options: SelectPromptOptions<T>): Promis
                     return;
                 }
                 const n = parseInt(trimmed, 10);
-                if (!isNaN(n) && n >= 1 && n <= choices.length) {
+                if (!Number.isNaN(n) && n >= 1 && n <= choices.length) {
                     rl.close();
                     resolve(choices[n - 1].value);
                     return;