# Appium Kepler Driver (v3.30.0, JavaScript): socket hang up error and vdcm list-methods only shows Usage

**URL:** <https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647>\
**Category:** Q&A\
**Created:** [October 28, 2025, 11:53am UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647 "2025-10-28T11:53:49Z")\
**Posts on this page:** 12\
**Page:** 1

<div class="post-metadata">

**Author:** ![Thimmanna](https://avatars.discourse-cdn.com/v4/letter/t/ecd19e/32.png) [@Thimmanna](https://community.amazondeveloper.com/u/Thimmanna)\
**Post date:** [October 28, 2025, 11:53am UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/1 "2025-10-28T11:53:49Z")

</div>

I’m running Appium tests written in **JavaScript (WebdriverIO)** against an **Amazon emulator and physical device** , but the app isn’t launching and JSON-RPC calls fail with a `"socket hang up"` error. Also, `vdcm list-methods` only shows the usage message instead of listing available RPC methods.

Environment:

- macOS (local dev machine)

- Node.js v20.15.1

- Appium Server 2.12.1 (local)

- WebdriverIO client (JavaScript)

- Emulator: `emulator-5554`

- Physical device: Fire TV Stick 4K (connected via adb)

- Command: `vda -s emulator-5554 shell "vdcm list-methods"`

- VDA Version:

- Appium driver:

Capabilities:

```auto
const capabilities = {
  platformName: 'Kepler',
  'appium:automationName': 'automation-toolkit/JSON-RPC',
  'kepler:device': 'vda://emulator-5554',
  'appium:appURL': 'com.amazon.keplervideoapp.main'
};

```

Expected Behavior:

- The emulator or device should launch the specified app successfully.

- JSON-RPC calls such as:

- should execute without socket or session errors.

- Running `vda -s emulator-5554 shell "vdcm list-methods"` should list available methods (`injectInputKeyEvent`, `captureScreenshot`, etc.).

Actual Behavior:

- App does not launch.

- Test script fails with:

- `vdcm list-methods` output:

- No RPC methods are shown.

- Same behavior after retries, app relaunches, or emulator/device restarts.

What I already tried:

1. Verified Appium–WebdriverIO compatibility.

2. Reinstalled Kepler driver (v3.30.0).

3. Confirmed device detection:

4. Checked network access and Appium endpoint (localhost:4723).

5. Tried multiple apps including `com.amazon.keplervideoapp.main`.

6. Restarted emulator and Appium server.

7. Tried with both emulator and physical device.

 ![Screenshot 2025-10-28 at 5.11.44 PM](https://d3mq594dkmpl37.cloudfront.net/original/2X/d/db845c147f291a1d447ebcdb5061e9002d359088.png)

---

<div class="post-metadata">

**Author:** ![Ivy](https://dhm3gbtzu79o6.cloudfront.net/user_avatar/community.amazondeveloper.com/ivy/32/5637_2.png) [@Ivy](https://community.amazondeveloper.com/u/Ivy)\
**Post date:** [October 28, 2025, 2:23pm UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/3 "2025-10-28T14:23:16Z")

</div>

Hey @Thimmanna

Welcome to Amazon Developer Community !  
Thanks for writing in, please allow me some time to look into this and I will update you as soon as I have something.

Warm regards,  
Ivy

---

<div class="post-metadata">

**Author:** ![Carlos\_Salas](https://avatars.discourse-cdn.com/v4/letter/c/f17d59/32.png) [@Carlos\_Salas](https://community.amazondeveloper.com/u/Carlos_Salas)\
**Post date:** [October 28, 2025, 4:00pm UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/4 "2025-10-28T16:00:41Z")

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Hi @Thimmanna,

Thank you for contacting us and sharing about your experience while working with Appium. What I can tell from your description is that automation-toolkit.service may not be running. Service requires a file activation as explained on [Set Up Testing with Appium | Design and Develop Vega Apps](https://developer.amazon.com/docs/vega/0.21/appium-setup.html#set-up-appium)

```auto
 touch /tmp/automation-toolkit.enable

```

Could you please first run the command above on your FireTV and/or Vega Virtual Device and try again? Please let me know if this solves your problem.

Thanks,

Carlos.

---

<div class="post-metadata">

**Author:** ![Thimmanna](https://avatars.discourse-cdn.com/v4/letter/t/ecd19e/32.png) [@Thimmanna](https://community.amazondeveloper.com/u/Thimmanna)\
**Post date:** [October 29, 2025, 7:32am UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/5 "2025-10-29T07:32:33Z")

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> [@Carlos\_Salas](#):
>
> `touch /tmp/automation-toolkit.enable`

 ![Screenshot 2025-10-29 at 12.59.45 PM](https://d3mq594dkmpl37.cloudfront.net/original/2X/0/061fcf6c04be71b332377627e509e63c62a72ed9.png)

device is connected, I did run the shared command, now i see the above message. I tried connecting the device multiple times.

---

<div class="post-metadata">

**Author:** ![Carlos\_Salas](https://avatars.discourse-cdn.com/v4/letter/c/f17d59/32.png) [@Carlos\_Salas](https://community.amazondeveloper.com/u/Carlos_Salas)\
**Post date:** [October 29, 2025, 3:23pm UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/6 "2025-10-29T15:23:10Z")

</div>

Hi @Thimmanna ,

I see from your previous post that you were testing on the Vega Virtual Device and this last screenshot is now from the FireTV. Also note that from the developer shell it’s not possible to use systemctl, hence the “error message”, so this may be a false positive.

Can you confirm if once following the file activation mechanism, did you attempted to use Appium?

Thanks,

Carlos.

---

<div class="post-metadata">

**Author:** ![Thimmanna](https://avatars.discourse-cdn.com/v4/letter/t/ecd19e/32.png) [@Thimmanna](https://community.amazondeveloper.com/u/Thimmanna)\
**Post date:** [October 30, 2025, 6:19am UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/7 "2025-10-30T06:19:42Z")

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Hi @Carlos_Salas ,

I was testing on both the Vega Virtual Device and a Fire TV—apologies for the confusion earlier. I’ve been following the file activation steps as described in the documentation linked below.

> **[Set Up Testing with Appium | Design and Develop Vega Apps](https://developer.amazon.com/docs/vega/0.21/appium-setup.html)**
>
> Open Beta Documentation Amazon offers this technical documentation as part of a pre-release, open beta. The features described might change as Amazon receives feedback an...

Please find the screen shot of the Vega Virtual device.

 ![Screenshot 2025-10-30 at 11.25.58 AM](https://d3mq594dkmpl37.cloudfront.net/original/2X/8/8ac3dfe8792c6aa1ddc35a27890c4a8aef7d52b4.png)

Please find my basic DPAD navigation script.

```auto
const { remote } = require('webdriverio');
const capabilities = {
  platformName: 'Kepler',
  'appium:automationName': 'automation-toolkit/JSON-RPC',
  'kepler:device': 'vda://emulator-5554',
  'appium:appURL': 'com.amazon.keplervideoapp.main',
};
const opts = {
  hostname: 'localhost',
  port: 4723,
  path: '/',
  logLevel: 'info',
  capabilities,
};

const test = async () => {
  const driver = await remote(opts);
  try {
    console.log('✅ App launched successfully!');
    await driver.executeScript('jsonrpc: injectInputKeyEvent', [
      {
        inputKeyEvent: {
          keyCode: 108,
          holdDuration: 1000,
        },
      },
    ]);
  } finally {
    await driver.deleteSession();
  }
};

test().catch(console.error);

```

The error i’m getting now is bit different.

 ![Screenshot 2025-10-30 at 11.47.21 AM](https://d3mq594dkmpl37.cloudfront.net/original/2X/c/c30afe258ebdf73627c010f160949eaeeb3004c9.png)

Can you please tell me what’s the problem in my script or am i missing something?

Thank you!

---

<div class="post-metadata">

**Author:** ![Wenguang\_Hu](https://avatars.discourse-cdn.com/v4/letter/w/cc9497/32.png) [@Wenguang\_Hu](https://community.amazondeveloper.com/u/Wenguang_Hu)\
**Post date:** [November 3, 2025, 6:48pm UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/8 "2025-11-03T18:48:24Z")

</div>

Hello @Thimmanna  
Maybe you do not need to pass the duration parameter.  
As python method  
it does not need duration parameter.

---

<div class="post-metadata">

**Author:** ![Thimmanna](https://avatars.discourse-cdn.com/v4/letter/t/ecd19e/32.png) [@Thimmanna](https://community.amazondeveloper.com/u/Thimmanna)\
**Post date:** [November 4, 2025, 5:38am UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/9 "2025-11-04T05:38:58Z")

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Hi @Wenguang_Hu ,

That didn’t solve the issue. Can anyone please share a working example of DAP navigation?

---

<div class="post-metadata">

**Author:** ![Wenguang\_Hu](https://avatars.discourse-cdn.com/v4/letter/w/cc9497/32.png) [@Wenguang\_Hu](https://community.amazondeveloper.com/u/Wenguang_Hu)\
**Post date:** [November 4, 2025, 3:33pm UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/10 "2025-11-04T15:33:23Z")

</div>

Hello @Thimmanna  
Do you have physical Fire TV Stick connected while using the emulator?  
Could you try to use emulator only or physical Fire TV only?

---

<div class="post-metadata">

**Author:** ![Wenguang\_Hu](https://avatars.discourse-cdn.com/v4/letter/w/cc9497/32.png) [@Wenguang\_Hu](https://community.amazondeveloper.com/u/Wenguang_Hu)\
**Post date:** [November 4, 2025, 3:36pm UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/11 "2025-11-04T15:36:32Z")

</div>

We have a example by python

> **[Appium Commands | Design and Develop Vega Apps](https://developer.amazon.com/docs/vega/0.21/appium-commands.html#d-pad-navigation)**
>
> Open Beta Documentation Amazon offers this technical documentation as part of a pre-release, open beta. The features described might change as Amazon receives feedback an...

---

<div class="post-metadata">

**Author:** ![Ivy](https://dhm3gbtzu79o6.cloudfront.net/user_avatar/community.amazondeveloper.com/ivy/32/5637_2.png) [@Ivy](https://community.amazondeveloper.com/u/Ivy)\
**Post date:** [November 28, 2025, 6:31am UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/12 "2025-11-28T06:31:54Z")

</div>

Closing this topic due to inactivity. @Thimmanna please feel free to contact us if you need further help.

---

<div class="post-metadata">

**Author:** ![Ivy](https://dhm3gbtzu79o6.cloudfront.net/user_avatar/community.amazondeveloper.com/ivy/32/5637_2.png) [@Ivy](https://community.amazondeveloper.com/u/Ivy)\
**Post date:** [November 28, 2025, 6:32am UTC](https://community.amazondeveloper.com/t/appium-kepler-driver-v3-30-0-javascript-socket-hang-up-error-and-vdcm-list-methods-only-shows-usage/24647/13 "2025-11-28T06:32:11Z")

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