fix: preserve underlying error message in input tool actions (#2792)

`handleActionError` previously rewrote every
`click`/`hover`/`fill`/`fill_form` failure as "The element did not
become interactive within the configured timeout", discarding the real
cause. It now keeps that wording only for an actual Puppeteer
`TimeoutError` and surfaces the underlying message otherwise, so e.g.
selecting a missing option now reports `Could not find option with text
"..."`.

src/third_party/index.ts

@@ -51,6 +51,7 @@ export {
   KnownDevices,
   CDPSessionEvent,
   ScreenRecorder,
+  TimeoutError,
 } from 'puppeteer-core';
 export {default as puppeteer} from 'puppeteer-core';
 export type * from 'puppeteer-core';

src/tools/input.ts

@@ -5,7 +5,7 @@
  */
 
 import type {McpContext} from '../McpContext.js';
-import {zod} from '../third_party/index.js';
+import {TimeoutError, zod} from '../third_party/index.js';
 import type {ElementHandle, KeyInput} from '../third_party/index.js';
 import type {TextSnapshotNode} from '../types.js';
 import {parseKey} from '../utils/keyboard.js';
@@ -35,8 +35,14 @@ const submitKeySchema = zod
 
 function handleActionError(error: unknown, uid: string) {
   logger?.('failed to act using a locator', error);
+  const reason =
+    error instanceof TimeoutError
+      ? 'The element did not become interactive within the configured timeout.'
+      : error instanceof Error
+        ? error.message
+        : String(error);
   throw new Error(
-    `Failed to interact with the element with uid ${uid}. The element did not become interactive within the configured timeout.`,
+    `Failed to interact with the element with uid ${uid}. ${reason}`,
     {
       cause: error,
     },

tests/tools/input.test.ts

@@ -588,6 +588,40 @@ describe('input', () => {
       });
     });
 
+    it('reports why filling out a select failed', async () => {
+      await withMcpContext(async (response, context, args) => {
+        const page = context.getSelectedMcpPage().pptrPage;
+        await page.setContent(
+          html`<select
+            ><option value="v1">one</option
+            ><option value="v2">two</option></select
+          >`,
+        );
+        context.getSelectedMcpPage().textSnapshot = await TextSnapshot.create(
+          context.getSelectedMcpPage(),
+        );
+        await assert.rejects(
+          () =>
+            fill(args).handler(
+              {
+                params: {
+                  // Options are matched by their text, not their value.
+                  uid: '1_1',
+                  value: 'v2',
+                },
+                page: context.getSelectedMcpPage(),
+              },
+              response,
+              context,
+            ),
+          {
+            message:
+              'Failed to interact with the element with uid 1_1. Could not find option with text "v2"',
+          },
+        );
+      });
+    });
+
     it('fills out a select option with an empty value by text', async () => {
       await withMcpContext(async (response, context, args) => {
         const page = context.getSelectedMcpPage().pptrPage;