fix: optimize token usage

docs/slim-tool-reference.md

@@ -1,6 +1,6 @@
 <!-- AUTO GENERATED DO NOT EDIT - run 'npm run docs' to update-->
 
-# Chrome DevTools MCP Slim Tool Reference (~368 cl100k_base tokens)
+# Chrome DevTools MCP Slim Tool Reference (~359 cl100k_base tokens)
 
 - **[Navigation automation](#navigation-automation)** (1 tools)
   - [`navigate`](#navigate)
@@ -12,29 +12,29 @@
 
 ### `navigate`
 
-**Description:** Load URL in the browser
+**Description:** Loads a URL.
 
 **Parameters:**
 
-- **url** (string) **(required)**: Page URL
+- **url** (string) **(required)**: URL to [`navigate`](#navigate) to.
 
 ---
 
 ## Debugging
 
 ### `evaluate`
 
-**Description:** [`Evaluate`](#evaluate) a JavaScript function on the last loaded page
+**Description:** Evaluates a JavaScript function.
 
 **Parameters:**
 
-- **fn** (string) **(required)**: A JavaScript function to be executed on the active page
+- **fn** (string) **(required)**: JS function to run on the page.
 
 ---
 
 ### `screenshot`
 
-**Description:** Take a [`screenshot`](#screenshot) of the active page.
+**Description:** Takes a [`screenshot`](#screenshot).
 
 **Parameters:** None
 

scripts/dump_tools.mjs

@@ -0,0 +1,24 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import {Client} from '@modelcontextprotocol/sdk/client/index.js';
+import {StdioClientTransport} from '@modelcontextprotocol/sdk/client/stdio.js';
+
+const transport = new StdioClientTransport({
+  command: 'node',
+  args: ['./build/src/index.js'],
+});
+
+const client = new Client(
+  {name: 'measurer', version: '1.0.0'},
+  {capabilities: {}},
+);
+await client.connect(transport);
+
+const toolsList = await client.listTools();
+const jsonString = JSON.stringify(toolsList.tools);
+console.log(jsonString);
+await client.close();

src/main.ts

@@ -72,6 +72,8 @@ const server = new McpServer(
     name: 'chrome_devtools',
     title: 'Chrome DevTools MCP server',
     version: VERSION,
+    description:
+      'All tools operate on the currently selected page. Many tools take a `uid` of an element from a page content snapshot.',
   },
   {capabilities: {logging: {}}},
 );

src/tools/ToolDefinition.ts

@@ -178,9 +178,7 @@ export const timeoutSchema = {
     .number()
     .int()
     .optional()
-    .describe(
-      `Maximum wait time in milliseconds. If set to 0, the default timeout will be used.`,
-    )
+    .describe(`Max wait time in ms. 0 for default.`)
     .transform(value => {
       return value && value <= 0 ? undefined : value;
     }),

src/tools/console.ts

@@ -39,8 +39,7 @@ const FILTERABLE_MESSAGE_TYPES: [
 
 export const listConsoleMessages = defineTool({
   name: 'list_console_messages',
-  description:
-    'List all console messages for the currently selected page since the last navigation.',
+  description: 'List all console messages since the last navigation.',
   annotations: {
     category: ToolCategory.DEBUGGING,
     readOnlyHint: true,
@@ -51,30 +50,22 @@ export const listConsoleMessages = defineTool({
       .int()
       .positive()
       .optional()
-      .describe(
-        'Maximum number of messages to return. When omitted, returns all requests.',
-      ),
+      .describe('Max messages to return. Omit for all.'),
     pageIdx: zod
       .number()
       .int()
       .min(0)
       .optional()
-      .describe(
-        'Page number to return (0-based). When omitted, returns the first page.',
-      ),
+      .describe('0-based page number. Omit for first page.'),
     types: zod
       .array(zod.enum(FILTERABLE_MESSAGE_TYPES))
       .optional()
-      .describe(
-        'Filter messages to only return messages of the specified resource types. When omitted or empty, returns all messages.',
-      ),
+      .describe('Filter by message type. Omit or empty for all.'),
     includePreservedMessages: zod
       .boolean()
       .default(false)
       .optional()
-      .describe(
-        'Set to true to return the preserved messages over the last 3 navigations.',
-      ),
+      .describe('Set to true for preserved messages over last 3 navigations.'),
   },
   handler: async (request, response) => {
     response.setIncludeConsoleData(true, {
@@ -96,9 +87,7 @@ export const getConsoleMessage = defineTool({
   schema: {
     msgid: zod
       .number()
-      .describe(
-        'The msgid of a console message on the page from the listed console messages',
-      ),
+      .describe('msgid of a console message from listed messages'),
   },
   handler: async (request, response) => {
     response.attachConsoleMessage(request.params.msgid);

src/tools/emulation.ts

@@ -18,7 +18,7 @@ const throttlingOptions: [string, ...string[]] = [
 
 export const emulate = defineTool({
   name: 'emulate',
-  description: `Emulates various features on the selected page.`,
+  description: `Emulates various features.`,
   annotations: {
     category: ToolCategory.EMULATION,
     readOnlyHint: false,
@@ -28,16 +28,14 @@ export const emulate = defineTool({
       .enum(throttlingOptions)
       .optional()
       .describe(
-        `Throttle network. Set to "No emulation" to disable. If omitted, conditions remain unchanged.`,
+        `Throttle network. "No emulation" to disable. Omit to keep unchanged.`,
       ),
     cpuThrottlingRate: zod
       .number()
       .min(1)
       .max(20)
       .optional()
-      .describe(
-        'Represents the CPU slowdown factor. Set the rate to 1 to disable throttling. If omitted, throttling remains unchanged.',
-      ),
+      .describe('CPU slowdown factor. 1 to disable. Omit to keep unchanged.'),
     geolocation: zod
       .object({
         latitude: zod
@@ -53,55 +51,41 @@ export const emulate = defineTool({
       })
       .nullable()
       .optional()
-      .describe(
-        'Geolocation to emulate. Set to null to clear the geolocation override.',
-      ),
+      .describe('Geolocation to emulate. null to clear override.'),
     userAgent: zod
       .string()
       .nullable()
       .optional()
-      .describe(
-        'User agent to emulate. Set to null to clear the user agent override.',
-      ),
+      .describe('User agent to emulate. null to clear override.'),
     colorScheme: zod
       .enum(['dark', 'light', 'auto'])
       .optional()
-      .describe(
-        'Emulate the dark or the light mode. Set to "auto" to reset to the default.',
-      ),
+      .describe('Emulate dark or light mode. "auto" to reset.'),
     viewport: zod
       .object({
-        width: zod.number().int().min(0).describe('Page width in pixels.'),
-        height: zod.number().int().min(0).describe('Page height in pixels.'),
+        width: zod.number().int().min(0).describe('Page width (px).'),
+        height: zod.number().int().min(0).describe('Page height (px).'),
         deviceScaleFactor: zod
           .number()
           .min(0)
           .optional()
-          .describe('Specify device scale factor (can be thought of as dpr).'),
+          .describe('Device scale factor (dpr).'),
         isMobile: zod
           .boolean()
           .optional()
-          .describe(
-            'Whether the meta viewport tag is taken into account. Defaults to false.',
-          ),
+          .describe('Use meta viewport tag. Default: false.'),
         hasTouch: zod
           .boolean()
           .optional()
-          .describe(
-            'Specifies if viewport supports touch events. This should be set to true for mobile devices.',
-          ),
+          .describe('Viewport supports touch. true for mobile.'),
         isLandscape: zod
           .boolean()
           .optional()
-          .describe(
-            'Specifies if viewport is in landscape mode. Defaults to false.',
-          ),
+          .describe('Landscape mode. Default: false.'),
       })
       .nullable()
       .optional()
-      .describe(
-        'Viewport to emulate. Set to null to reset to the default viewport.',
-      ),
+      .describe('Viewport to emulate. null to reset.'),
   },
   handler: async (request, _response, context) => {
     await context.emulate(request.params);

src/tools/extensions.ts

@@ -20,9 +20,7 @@ export const installExtension = defineTool({
     conditions: [EXTENSIONS_CONDITION],
   },
   schema: {
-    path: zod
-      .string()
-      .describe('Absolute path to the unpacked extension folder.'),
+    path: zod.string().describe('Absolute path to unpacked extension.'),
   },
   handler: async (request, response, context) => {
     const {path} = request.params;
@@ -40,7 +38,7 @@ export const uninstallExtension = defineTool({
     conditions: [EXTENSIONS_CONDITION],
   },
   schema: {
-    id: zod.string().describe('ID of the extension to uninstall.'),
+    id: zod.string().describe('ID of extension to uninstall.'),
   },
   handler: async (request, response, context) => {
     const {id} = request.params;
@@ -51,8 +49,7 @@ export const uninstallExtension = defineTool({
 
 export const listExtensions = defineTool({
   name: 'list_extensions',
-  description:
-    'Lists all extensions via this server, including their name, ID, version, and enabled status.',
+  description: 'Lists all extensions with name, ID, version, and status.',
   annotations: {
     category: ToolCategory.EXTENSIONS,
     readOnlyHint: true,
@@ -73,7 +70,7 @@ export const reloadExtension = defineTool({
     conditions: [EXTENSIONS_CONDITION],
   },
   schema: {
-    id: zod.string().describe('ID of the extension to reload.'),
+    id: zod.string().describe('ID of extension to reload.'),
   },
   handler: async (request, response, context) => {
     const {id} = request.params;