mcp-playwright

Instructions

Implementation Reference

• src/tools/browser/visiblePage.ts:12-66 (handler)

  The execute method of VisibleTextTool class that performs the core logic: evaluates JavaScript on the page using TreeWalker to collect visible text nodes (excluding hidden elements), trims and concatenates the text, applies truncation if necessary, and returns the result.

  async execute(args: any, context: ToolContext): Promise<ToolResponse> {
    // Check if browser is available
    if (!context.browser || !context.browser.isConnected()) {
      // If browser is not connected, we need to reset the state to force recreation
      resetBrowserState();
      return createErrorResponse(
        "Browser is not connected. The connection has been reset - please retry your navigation."
      );
    }
  
    // Check if page is available and not closed
    if (!context.page || context.page.isClosed()) {
      return createErrorResponse(
        "Page is not available or has been closed. Please retry your navigation."
      );
    }
    return this.safeExecute(context, async (page) => {
      try {
        const visibleText = await page!.evaluate(() => {
          const walker = document.createTreeWalker(
            document.body,
            NodeFilter.SHOW_TEXT,
            {
              acceptNode: (node) => {
                const style = window.getComputedStyle(node.parentElement!);
                return (style.display !== "none" && style.visibility !== "hidden")
                  ? NodeFilter.FILTER_ACCEPT
                  : NodeFilter.FILTER_REJECT;
              },
            }
          );
          let text = "";
          let node;
          while ((node = walker.nextNode())) {
            const trimmedText = node.textContent?.trim();
            if (trimmedText) {
              text += trimmedText + "\n";
            }
          }
          return text.trim();
        });
        // Truncate logic
        const maxLength = typeof args.maxLength === 'number' ? args.maxLength : 20000;
        let output = visibleText;
        let truncated = false;
        if (output.length > maxLength) {
          output = output.slice(0, maxLength) + '\n[Output truncated due to size limits]';
          truncated = true;
        }
        return createSuccessResponse(`Visible text content:\n${output}`);
      } catch (error) {
        return createErrorResponse(`Failed to get visible text content: ${(error as Error).message}`);
      }
    });
  }

• src/tools.ts:343-350 (schema)

  Tool definition including name, description, and empty inputSchema (no parameters required). Part of createToolDefinitions() array.

    name: "playwright_get_visible_text",
    description: "Get the visible text content of the current page",
    inputSchema: {
      type: "object",
      properties: {},
      required: [],
    },
  },

• src/toolHandler.ts:517-518 (registration)

  Switch case in handleToolCall that dispatches to the VisibleTextTool instance's execute method.

  case "playwright_get_visible_text":
    return await visibleTextTool.execute(args, context);

• src/toolHandler.ts:332-332 (registration)

  Instantiation of the VisibleTextTool class instance used for execution.

  if (!visibleTextTool) visibleTextTool = new VisibleTextTool(server);

• src/toolHandler.ts:35-35 (registration)

  Import of the VisibleTextTool class from its implementation file.

  } from './tools/browser/visiblePage.js';