diff --git a/src/services/browser-capture.test.ts b/src/services/browser-capture.test.ts
new file mode 100644
index 000000000..afb0ef707
--- /dev/null
+++ b/src/services/browser-capture.test.ts
@@ -0,0 +1,109 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { existsSync, writeFileSync } from "node:fs";
+
+// Mock dependencies
+vi.mock("node:fs", () => ({
+  writeFileSync: vi.fn(),
+  existsSync: vi.fn(),
+}));
+
+vi.mock("node:os", () => ({
+  tmpdir: () => "/tmp",
+}));
+
+const mockCDPSession = {
+  on: vi.fn(),
+  send: vi.fn(),
+};
+
+const mockPage = {
+  setViewport: vi.fn(),
+  goto: vi.fn(),
+  createCDPSession: vi.fn().mockResolvedValue(mockCDPSession),
+};
+
+const mockBrowser = {
+  newPage: vi.fn().mockResolvedValue(mockPage),
+  close: vi.fn(),
+};
+
+const mockLaunch = vi.fn().mockResolvedValue(mockBrowser);
+
+vi.mock("puppeteer-core", () => ({
+  default: {
+    launch: mockLaunch,
+  },
+}));
+
+import {
+  startBrowserCapture,
+  stopBrowserCapture,
+  isBrowserCaptureRunning,
+  hasFrameFile,
+  FRAME_FILE,
+} from "./browser-capture";
+
+describe("browser-capture", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  afterEach(async () => {
+    await stopBrowserCapture();
+  });
+
+  it("should start browser capture", async () => {
+    await startBrowserCapture({ url: "http://example.com" });
+    expect(mockLaunch).toHaveBeenCalledWith(expect.objectContaining({
+      headless: true,
+      args: expect.arrayContaining(["--no-sandbox", "--disable-gpu"]),
+    }));
+    expect(mockBrowser.newPage).toHaveBeenCalled();
+    expect(mockPage.goto).toHaveBeenCalledWith("http://example.com", expect.objectContaining({ waitUntil: "domcontentloaded" }));
+    expect(mockPage.createCDPSession).toHaveBeenCalled();
+    expect(mockCDPSession.send).toHaveBeenCalledWith("Page.startScreencast", expect.objectContaining({
+      format: "jpeg",
+      quality: 70,
+    }));
+    expect(isBrowserCaptureRunning()).toBe(true);
+  });
+
+  it("should not start if already running", async () => {
+    await startBrowserCapture({ url: "http://example.com" });
+    mockLaunch.mockClear();
+    await startBrowserCapture({ url: "http://example.com" });
+    expect(mockLaunch).not.toHaveBeenCalled();
+  });
+
+  it("should handle screencast frames", async () => {
+    await startBrowserCapture({ url: "http://example.com" });
+
+    // Simulate frame event
+    // The implementation uses: cdp.on("Page.screencastFrame", ...)
+    const onCall = mockCDPSession.on.mock.calls.find((call: any[]) => call[0] === "Page.screencastFrame");
+    expect(onCall).toBeDefined();
+
+    const onCallback = onCall[1];
+    const frameData = { data: Buffer.from("test-image-data").toString("base64"), sessionId: 123 };
+    await onCallback(frameData);
+
+    expect(writeFileSync).toHaveBeenCalledWith(FRAME_FILE, expect.any(Buffer));
+    expect(mockCDPSession.send).toHaveBeenCalledWith("Page.screencastFrameAck", { sessionId: 123 });
+  });
+
+  it("should stop browser capture", async () => {
+    await startBrowserCapture({ url: "http://example.com" });
+    await stopBrowserCapture();
+    expect(mockBrowser.close).toHaveBeenCalled();
+    expect(isBrowserCaptureRunning()).toBe(false);
+  });
+
+  it("should check if frame file exists", () => {
+    vi.mocked(existsSync).mockReturnValue(true);
+    expect(hasFrameFile()).toBe(true);
+    expect(existsSync).toHaveBeenCalledWith(FRAME_FILE);
+
+    vi.mocked(existsSync).mockReturnValue(false);
+    expect(hasFrameFile()).toBe(false);
+  });
+});