mcp-uimax

Instructions

Implementation Reference

• src/tools/screenshot.ts:17-50 (handler)

  The handler function that executes the screenshot capture logic using a headless browser.

  export async function captureScreenshot(
    input: ScreenshotInput
  ): Promise<ScreenshotResult> {
    const width = input.width ?? 1440;
    const height = input.height ?? 900;
    const fullPage = input.fullPage ?? true;
    const delay = input.delay ?? 1000;
    const deviceScaleFactor = input.deviceScaleFactor ?? 2;
  
    const page = await createPage(width, height, deviceScaleFactor);
  
    try {
      await navigateAndWait(page, input.url, delay);
  
      const screenshotBuffer = await page.screenshot({
        type: "png",
        fullPage,
        encoding: "binary",
      });
  
      const base64 = Buffer.from(screenshotBuffer).toString("base64");
  
      return {
        base64,
        mimeType: "image/png",
        width,
        height,
        url: input.url,
        timestamp: new Date().toISOString(),
      };
    } finally {
      await closePage(page);
    }
  }

• src/tools/screenshot.ts:4-11 (schema)

  Type definition for the input parameters required by the screenshot tool.

  export interface ScreenshotInput {
    readonly url: string;
    readonly width?: number;
    readonly height?: number;
    readonly fullPage?: boolean;
    readonly delay?: number;
    readonly deviceScaleFactor?: number;
  }

• src/server.ts:262-268 (registration)

  Registration of the "screenshot" tool in the MCP server.

  server.tool(
    "screenshot",
    "Capture a screenshot of a webpage. Returns a PNG image that you can visually analyze for design issues, layout problems, and UI quality.",
    {
      url: z.string().url().describe("URL of the page to screenshot (e.g., http://localhost:3000)"),
      width: z.number().optional().default(1440).describe("Viewport width in pixels"),
      height: z.number().optional().default(900).describe("Viewport height in pixels"),