feat: get state from the open DevTools window

Author: OrKoN

src/McpContext.ts

@@ -337,12 +337,13 @@ export class McpContext implements Context {
       );
     });
 
-    await this.#detectOpenDevToolsWindows(allPages);
+    await this.detectOpenDevToolsWindows();
 
     return this.#pages;
   }
 
-  async #detectOpenDevToolsWindows(pages: Page[]) {
+  async detectOpenDevToolsWindows() {
+    const pages = await this.browser.pages();
     this.#pageToDevToolsPage = new Map<Page, Page>();
     for (const devToolsPage of pages) {
       if (devToolsPage.url().startsWith('devtools://')) {
@@ -376,6 +377,46 @@ export class McpContext implements Context {
   getDevToolsPage(page: Page): Page | undefined {
     return this.#pageToDevToolsPage.get(page);
   }
+  
+  async getDevToolsContextData(): Promise<undefined|{requestId?: number}> {
+    try {
+      const selectedPage = this.getSelectedPage();
+      const devtoolsPage = this.getDevToolsPage(selectedPage);
+      if (devtoolsPage) {
+        const cdpRequestId = await devtoolsPage.evaluate(async () => {
+          // @ts-expect-error no types
+          const UI = await import('/bundled/ui/legacy/legacy.js');
+          // @ts-expect-error no types
+          const SDK = await import('/bundled/core/sdk/sdk.js');
+          const request = UI.Context.Context.instance().flavor(SDK.NetworkRequest.NetworkRequest);
+          return request?.requestId();
+        });
+        let requestId: number|undefined;
+        if (!cdpRequestId) {
+          console.error('no context request');
+          return;
+        }
+
+        const request = this.#networkCollector.find(selectedPage, (request) => {
+            // @ts-expect-error id is internal.
+            return request.id === cdpRequestId;
+          });
+        if (!request) {
+          console.error('no collected request for ' + cdpRequestId);
+          return;
+        }
+        requestId = this.#networkCollector.getIdForResource(request);
+        return {
+          requestId,
+        }
+      } else {
+        console.error('no devtools page deteched');
+      }
+    } catch (err) {
+      console.error('error getting devtools data', err);
+    }
+    return;
+  }
 
   /**
    * Creates a text snapshot of a page.

src/McpResponse.ts

@@ -291,11 +291,15 @@ export class McpResponse implements Response {
       );
     }
 
+
+    const devToolsData = await context.getDevToolsContextData();
+
     return this.format(toolName, context, {
       bodies,
       consoleData,
       consoleListData,
       formattedSnapshot,
+      devToolsData,
     });
   }
 
@@ -310,13 +314,19 @@ export class McpResponse implements Response {
       consoleData: ConsoleMessageData | undefined;
       consoleListData: ConsoleMessageData[] | undefined;
       formattedSnapshot: string | undefined;
+      devToolsData?: {requestId?: number},
     },
   ): Array<TextContent | ImageContent> {
     const response = [`# ${toolName} response`];
     for (const line of this.#textResponseLines) {
       response.push(line);
     }
 
+    if (data.devToolsData?.requestId) {
+      response.push('## DevTools context');
+      response.push(`Network request reqid=${data.devToolsData?.requestId} is currently being inspected by the user in DevTools.`)
+    }
+
     const networkConditions = context.getNetworkConditions();
     if (networkConditions) {
       response.push(`## Network emulation`);

src/PageCollector.ts

@@ -173,6 +173,22 @@ export class PageCollector<T> {
 
     throw new Error('Request not found for selected page');
   }
+
+  find(page: Page, filter: (item: T) => boolean): T|undefined {
+    const navigations = this.storage.get(page);
+    if (!navigations) {
+      return;
+    }
+
+    for (const navigation of navigations) {
+      for (const collected of navigation) {
+        if (filter(collected)) {
+          return collected;
+        }
+      }
+    }
+    return;
+  }
 }
 
 export class NetworkCollector extends PageCollector<HTTPRequest> {

src/main.ts

@@ -129,6 +129,7 @@ function registerTool(tool: ToolDefinition): void {
       try {
         logger(`${tool.name} request: ${JSON.stringify(params, null, '  ')}`);
         const context = await getContext();
+        await context.detectOpenDevToolsWindows();
         const response = new McpResponse();
         await tool.handler(
           {