From 2211e19ffe6fa6668821879c31b858120f95fad9 Mon Sep 17 00:00:00 2001
From: miguel <miguelg71921@gmail.com>
Date: Tue, 4 Nov 2025 16:47:33 -0800
Subject: [PATCH 1/2] Add page.sendCDP

---
 .changeset/early-brooms-draw.md         |  5 +++++
 packages/core/lib/v3/understudy/page.ts | 26 +++++++++++++++++++++++++
 2 files changed, 31 insertions(+)
 create mode 100644 .changeset/early-brooms-draw.md

diff --git a/.changeset/early-brooms-draw.md b/.changeset/early-brooms-draw.md
new file mode 100644
index 000000000..af7b7ce04
--- /dev/null
+++ b/.changeset/early-brooms-draw.md
@@ -0,0 +1,5 @@
+---
+"@browserbasehq/stagehand": patch
+---
+
+Add a page.sendCDP method
diff --git a/packages/core/lib/v3/understudy/page.ts b/packages/core/lib/v3/understudy/page.ts
index a9dd0751e..95da31f08 100644
--- a/packages/core/lib/v3/understudy/page.ts
+++ b/packages/core/lib/v3/understudy/page.ts
@@ -478,6 +478,32 @@ export class Page {
     return this._targetId;
   }
 
+  /**
+   * Send a CDP command through the main session.
+   * Allows external consumers to execute arbitrary Chrome DevTools Protocol commands.
+   *
+   * @param method - The CDP method name (e.g., "Page.enable", "Runtime.evaluate")
+   * @param params - Optional parameters for the CDP command
+   * @returns Promise resolving to the typed CDP response
+   *
+   * @example
+   * // Enable the Runtime domain
+   * await page.sendCDP("Runtime.enable");
+   *
+   * @example
+   * // Evaluate JavaScript with typed response
+   * const result = await page.sendCDP<Protocol.Runtime.EvaluateResponse>(
+   *   "Runtime.evaluate",
+   *   { expression: "1 + 1" }
+   * );
+   */
+  public async sendCDP<T = unknown>(
+    method: string,
+    params?: object,
+  ): Promise<T> {
+    return this.mainSession.send<T>(method, params);
+  }
+
   /** Seed the cached URL before navigation events converge. */
   public seedCurrentUrl(url: string | undefined | null): void {
     if (!url) return;

From e668c48f4feb679db091799076970daabb6b76f0 Mon Sep 17 00:00:00 2001
From: miguel <miguelg71921@gmail.com>
Date: Tue, 4 Nov 2025 17:00:23 -0800
Subject: [PATCH 2/2] unit test

---
 .../core/lib/v3/tests/page-send-cdp.spec.ts   | 57 +++++++++++++++++++
 1 file changed, 57 insertions(+)
 create mode 100644 packages/core/lib/v3/tests/page-send-cdp.spec.ts

diff --git a/packages/core/lib/v3/tests/page-send-cdp.spec.ts b/packages/core/lib/v3/tests/page-send-cdp.spec.ts
new file mode 100644
index 000000000..4affbc75d
--- /dev/null
+++ b/packages/core/lib/v3/tests/page-send-cdp.spec.ts
@@ -0,0 +1,57 @@
+import { test, expect } from "@playwright/test";
+import { V3 } from "../v3";
+import { v3TestConfig } from "./v3.config";
+
+test.describe("Page sendCDP method", () => {
+  let v3: V3;
+
+  test.beforeEach(async () => {
+    v3 = new V3(v3TestConfig);
+    await v3.init();
+  });
+
+  test.afterEach(async () => {
+    await v3?.close?.().catch(() => {});
+  });
+
+  test("sends CDP commands and requires domain to be enabled first", async () => {
+    const page = v3.context.pages()[0];
+    await page.goto("https://example.com");
+
+    // Try to add a virtual authenticator without enabling WebAuthn first
+    // This should fail because the domain needs to be enabled
+    await expect(
+      page.sendCDP("WebAuthn.addVirtualAuthenticator", {
+        options: {
+          protocol: "ctap2",
+          transport: "usb",
+          hasResidentKey: false,
+          hasUserVerification: false,
+          isUserVerified: false,
+        },
+      }),
+    ).rejects.toThrow();
+
+    // Enable the WebAuthn domain
+    await page.sendCDP("WebAuthn.enable");
+
+    // Now adding a virtual authenticator should succeed
+    const result = await page.sendCDP<{ authenticatorId: string }>(
+      "WebAuthn.addVirtualAuthenticator",
+      {
+        options: {
+          protocol: "ctap2",
+          transport: "usb",
+          hasResidentKey: false,
+          hasUserVerification: false,
+          isUserVerified: false,
+        },
+      },
+    );
+
+    // Verify we got an authenticator ID back
+    expect(result).toHaveProperty("authenticatorId");
+    expect(typeof result.authenticatorId).toBe("string");
+    expect(result.authenticatorId.length).toBeGreaterThan(0);
+  });
+});