mcp-playwright

Instructions

Implementation Reference

• src/tools/browser/output.ts:13-49 (handler)

  Implements the core logic: generates PDF options from args, calls page.pdf(), registers the saved PDF as an MCP resource, and returns a success response with the resource URI.

  async execute(args: any, context: ToolContext): Promise<ToolResponse> {
    return this.safeExecute(context, async (page) => {
      const filename = args.filename || "page.pdf";
      const options = {
        path: path.resolve(args.outputPath || ".", filename),
        format: args.format || "A4",
        printBackground: args.printBackground !== false,
        margin: args.margin || {
          top: "1cm",
          right: "1cm",
          bottom: "1cm",
          left: "1cm",
        },
      };
  
      await page.pdf(options);
      let resourceLink: Awaited<ReturnType<typeof registerFileResource>> | undefined;
      let savedLocation = options.path;
      try {
        resourceLink = await registerFileResource({
          filePath: options.path,
          name: filename,
          mimeType: "application/pdf",
          server: this.server,
        });
        if (resourceLink?.uri) {
          savedLocation = resourceLink.uri;
        }
      } catch (error) {
        console.warn("Failed to register PDF as resource:", error);
      }
      return {
        ...createSuccessResponse(`Saved page as PDF: ${savedLocation}`),
        ...(resourceLink ? { resourceLinks: [resourceLink] } : {}),
      };
    });
  }

• src/tools.ts:455-477 (schema)

  Defines the tool name, description, and input schema for validation including required outputPath and optional PDF options.

    name: "playwright_save_as_pdf",
    description: "Save the current page as a PDF file",
    inputSchema: {
      type: "object",
      properties: {
        outputPath: { type: "string", description: "Directory path where PDF will be saved" },
        filename: { type: "string", description: "Name of the PDF file (default: page.pdf)" },
        format: { type: "string", description: "Page format (e.g. 'A4', 'Letter')" },
        printBackground: { type: "boolean", description: "Whether to print background graphics" },
        margin: {
          type: "object",
          description: "Page margins",
          properties: {
            top: { type: "string" },
            right: { type: "string" },
            bottom: { type: "string" },
            left: { type: "string" },
          },
        },
      },
      required: ["outputPath"],
    },
  },

• src/toolHandler.ts:649-650 (registration)

  Dispatches tool calls matching 'playwright_save_as_pdf' to the SaveAsPdfTool instance's execute method in the main handleToolCall switch statement.

  case "playwright_save_as_pdf":
    return await saveAsPdfTool.execute(args, context);

• src/tools.ts:514-514 (registration)

  Includes the tool in BROWSER_TOOLS array, which determines when to ensure browser context is available before execution.

  "playwright_save_as_pdf",

• src/toolHandler.ts:34-34 (registration)

  Imports the SaveAsPdfTool class required for instantiation and execution.

  import { SaveAsPdfTool } from "./tools/browser/output.js";