diff --git a/README.md b/README.md
index d005a3b..d8936fb 100644
--- a/README.md
+++ b/README.md
@@ -39,7 +39,9 @@ Options:
 - `stderr` — writable stream to use instead of `process.stderr`. With `nodeWasi`, only streams with a numeric `fd` property are supported.
 - `buffer` — when `true`, capture stdout and stderr and return them as strings in the result (`{ code, stdout, stderr }`). Custom `stdout`/`stderr` streams take precedence over buffering for the corresponding channel (default: `false`).
 - `env` — environment variables passed to the WASI instance (default: `process.env`).
-- `preopens` — WASI preopened directories mapping guest paths to host paths (default: `{ ".": process.cwd() }`). Absolute paths passed as args are auto-added as preopens.
+- `preopens` — WASI preopened directories mapping guest paths to host paths (default: `{ ".": process.cwd() }`, except when `cwd` is `/` or `\\` in which case it's `{}`). Absolute paths passed as args are auto-added as preopens.
+  
+  **Note:** When your app is launched from a GUI (macOS Finder, Windows Explorer, etc.) without a terminal, `process.cwd()` may be `/` (root). In this case, the default preopens excludes `"."` to avoid permission/sandbox issues. You should provide explicit absolute paths in the `preopens` option or as arguments when running in GUI environments.
 - `returnOnExit` — when `true`, `proc_exit` returns the exit code instead of terminating the process (default: `true`).
 - `nodeWasi` — use Node's built-in `node:wasi` instead of the bundled WASI shim. Enabled by default on Node.js for best performance; automatically disabled on Bun and Deno where `node:wasi` is not available, falling back to the bundled shim. Can also be forced on via `RIPGREP_NODE_WASI=1`.
 
diff --git a/lib/index.mjs b/lib/index.mjs
index bcee43d..984042b 100644
--- a/lib/index.mjs
+++ b/lib/index.mjs
@@ -1,15 +1,35 @@
 import { fileURLToPath } from "node:url";
-import { isAbsolute, resolve } from "node:path";
+import { isAbsolute, resolve, parse } from "node:path";
 
 export const rgPath = fileURLToPath(new URL("./rg.mjs", import.meta.url));
 
+function isRootPath(cwd) {
+  // Unix: "/"
+  // Windows: "C:\\", "D:\\", "C:/", or just "\\"
+  if (cwd === "/" || cwd === "\\") return true;
+  const parsed = parse(cwd);
+  return parsed.root === cwd;
+}
+
+function getDefaultPreopens() {
+  const cwd = process.cwd();
+  // Skip mapping "." to cwd when it's root - this commonly happens
+  // when apps are launched from GUI (macOS Finder, Windows Explorer, etc.)
+  // without a terminal. In these cases, "/" or "C:\\" is rarely the intended
+  // search directory and can cause permission/sandbox issues.
+  if (isRootPath(cwd)) {
+    return {};
+  }
+  return { ".": cwd };
+}
+
 export async function ripgrep(args = [], options = {}) {
   let {
     stdout,
     stderr,
     buffer = false,
     env = process.env,
-    preopens = { ".": process.cwd() },
+    preopens = getDefaultPreopens(),
     returnOnExit = true,
     nodeWasi = getDefaultNodeWasi(),
   } = options;
diff --git a/test/ripgrep.test.mjs b/test/ripgrep.test.mjs
index a43de25..652af5c 100644
--- a/test/ripgrep.test.mjs
+++ b/test/ripgrep.test.mjs
@@ -128,6 +128,30 @@ describe("ripgrep", () => {
     expect(res.stdout).toMatch(/^ripgrep \d+/);
   });
 
+  it("works when cwd is root (regression test for GUI launcher issue)", async () => {
+    // When apps are launched from GUI (Finder, Explorer, etc.), cwd may be "/"
+    // This should not break ripgrep - it should require explicit paths
+    const originalCwd = process.cwd();
+    const absHello = originalCwd + "/" + HELLO;
+
+    // Only run this test if we can chdir to root
+    try {
+      process.chdir("/");
+    } catch {
+      // Skip if we can't chdir to root (permissions)
+      return;
+    }
+
+    try {
+      // With cwd=/, relative paths won't work, but absolute paths should
+      const res = await ripgrep(["hello", absHello], { buffer: true });
+      expect(res.code).toBe(0);
+      expect(res.stdout).toContain("hello ripgrep world");
+    } finally {
+      process.chdir(originalCwd);
+    }
+  });
+
   it("searches with explicit --color=never", async () => {
     const res = await ripgrep(["--color=never", "hello", HELLO], {
       buffer: true,