diff --git a/skills/sherpa-onnx-tts/bin/sherpa-onnx-tts b/skills/sherpa-onnx-tts/bin/sherpa-onnx-tts
index 82a7cceaf16..1d7b29974e0 100755
--- a/skills/sherpa-onnx-tts/bin/sherpa-onnx-tts
+++ b/skills/sherpa-onnx-tts/bin/sherpa-onnx-tts
@@ -1,8 +1,8 @@
 #!/usr/bin/env node
 
-const fs = require("node:fs");
-const path = require("node:path");
-const { spawnSync } = require("node:child_process");
+import fs from "node:fs";
+import path from "node:path";
+import { spawnSync } from "node:child_process";
 
 function usage(message) {
   if (message) {
diff --git a/src/agents/skills.sherpa-onnx-tts-bin.test.ts b/src/agents/skills.sherpa-onnx-tts-bin.test.ts
new file mode 100644
index 00000000000..a8453366222
--- /dev/null
+++ b/src/agents/skills.sherpa-onnx-tts-bin.test.ts
@@ -0,0 +1,23 @@
+import { spawnSync } from "node:child_process";
+import path from "node:path";
+import { describe, expect, it } from "vitest";
+
+describe("skills/sherpa-onnx-tts bin script", () => {
+  it("loads as ESM and falls through to usage output when env is missing", () => {
+    const scriptPath = path.resolve(
+      process.cwd(),
+      "skills",
+      "sherpa-onnx-tts",
+      "bin",
+      "sherpa-onnx-tts",
+    );
+    const result = spawnSync(process.execPath, [scriptPath], {
+      encoding: "utf8",
+    });
+
+    expect(result.status).toBe(1);
+    expect(result.stderr).toContain("Missing runtime/model directory.");
+    expect(result.stderr).toContain("Usage: sherpa-onnx-tts");
+    expect(result.stderr).not.toContain("require is not defined in ES module scope");
+  });
+});