health_check

Instructions

Implementation Reference

• packages/mcp-server/src/tools/health.ts:4-33 (handler)

  The actual handler function for the health_check tool. It launches a browser via Puppeteer, returns version info, platform details, and outDir, or an error if the browser fails to launch.

  export async function handleHealthCheck(version: string) {
    try {
      const browser = await launchBrowser();
      const browserVersion = await browser.version();
      await browser.close();
      return {
        content: [{
          type: "text" as const,
          text: JSON.stringify({
            ok: true,
            serverVersion: version,
            browser: browserVersion,
            platform: process.platform,
            arch: process.arch,
            nodeVersion: process.version,
            outDir: defaultOutDir(),
            pid: process.pid,
          }, null, 2),
        }],
      };
    } catch (err: any) {
      return {
        content: [{
          type: "text" as const,
          text: JSON.stringify({ ok: false, error: err.message, platform: process.platform }),
        }],
        isError: true,
      };
    }
  }

• packages/mcp-server/src/server.ts:60-66 (registration)

  Registration of the health_check tool on the McpServer. It has an empty schema (no inputs), read-only hint, and invokes handleHealthCheck(VERSION).

  server.tool(
    "health_check",
    "Verify Puppeteer/Chromium can launch. Use when render fails.",
    {},
    { readOnlyHint: true, destructiveHint: false, idempotentHint: true, openWorldHint: false },
    async () => handleHealthCheck(VERSION),
  );

• packages/cli/src/browser.ts:18-31 (helper)

  The launchBrowser helper function used by handleHealthCheck to launch Puppeteer/Chromium with secure sandbox args.

  export async function launchBrowser(): Promise<Browser> {
    try {
      return await puppeteer.launch({
        headless: true,
        args: LAUNCH_ARGS,
        timeout: 30000,
      });
    } catch (err: any) {
      throw new Error(
        `browser_launch_failed: ${err.message}. ` +
        `Ensure Chromium is available. On containers, verify /dev/shm size or set --disable-dev-shm-usage.`,
      );
    }
  }

• packages/mcp-server/src/helpers.ts:6-29 (helper)

  The defaultOutDir helper function used by handleHealthCheck to determine the output directory path.

  export function defaultOutDir(): string {
    if (process.env.SLIDESHOT_OUTPUT_DIR) {
      return process.env.SLIDESHOT_OUTPUT_DIR;
    }
  
    const home = os.homedir();
  
    const desktop = path.join(home, "Desktop");
    if (fs.existsSync(desktop)) {
      return path.join(desktop, "slideshot-output");
    }
  
    const downloads = path.join(home, "Downloads");
    if (fs.existsSync(downloads)) {
      return path.join(downloads, "slideshot-output");
    }
  
    return path.join(os.tmpdir(), "slideshot-output");
  }
  
  export function resolveFormats(formats?: ImageFormat[]): ImageFormat[] {
    if (!formats || formats.length === 0) return ["pdf"];
    return formats;
  }