Resolve Vega Extension and CLI Issues

This page provides solutions to common issues you might encounter when using Vega Studio with VS Code. If you don't find a solution to your specific problem here, post an issue in Developer Forum for additional support.

Compound debug configuration in VS Code doesn't work

Cause: VS Code compound configurations may not initialize both debuggers correctly in the expected sequence.

Solution: As a workaround, complete these steps:

1. In the VS Code activity bar, select the Run and Debug icon.
2. From the given options, select (script) Attach and Start Debugging (F5). Wait until the script attaches to the app.
3. Select (native) Attach and Start Debugging (F5). Wait until the native attaches to the app.
4. Debug both script and native.

Failed to run command

Error message: Failed to execute command: Following command failed, checks logs - '<Command that failed>'

Cause: The Vega Studio extension runs certain commands in the background to provide functionality. Occasionally, one of these background commands might not run properly.

Solution: To determine the reason for the error, navigate to Output > Kepler.

Can't locate app package ID

Cause: The app ID is stored in the manifest.toml file but the location may not be clear.

Solution:

1. Open your app's manifest.toml file.
2. Look for the [package] section.

3. The id field contains your app's package ID.

   [package]
   title = "Basic UI React Naive Application"
   version = "0.1.0"
   id = "com.amazondeveloper.myvegaapp"
   # com.amazondeveloper.myvegaapp is the app's package ID
   

Vega Studio doesn't show content in the "Build Modes" view of the Vega sidebar.

Cause: VS Code cache corruption or multiple VS Code instances running simultaneously.

Solution:

1. Stop all instances of VS Code, including hidden ones.

   • macOS: Apple > Force Quit > Select all VS Codes instances > Force Quit.
   • Ubuntu: Run killall code.

2. Clear VS Codes caches

   Mac OS

   1. Navigate to ~/Library/Application Support/Code.
   2. Delete these folders: Cache, CachedData, CachedExtensions, CachedExtensionVSIXs (if exists), and Code Cache.

   Ubuntu

   1. Navigate to $HOME/.config/Code/User
   2. Delete these folders: Cache, CachedData, CachedExtensions, CachedExtensionVSIXs (if exists), and Code Cache.

3. Restart VS Code.

Tab navigation order incorrect in Build Modes

Cause: VS Code places the panel between the Status bar and Window header controls by design.

Solution: This is expected VS Code behavior. Use mouse navigation or keyboard shortcuts to navigate the Build Modes panel.

Focus indicator not visible in Build Modes panel

Cause: VS Code focus indicator behavior for custom panels.

Solution: This is expected behavior. The panel is still functional even without the visual focus indicator.

Vega commands fail to run in VS Code extension

Cause: Version compatibility issues between VS Code and the Vega extension, or outdated extension installation.

The Vega SDK installs the latest VS Code version on your machine. VS Code might update automatically to a later version, creating an error when you attempt to run Vega commands with Vega Studio extension.

You might also encounter an error if you have a previous version of the Vega Studio extension installed on VS Code.

Solution:

Uninstall the existing extension

1. Open VS Code.

2. Navigate to Settings > Extensions from the activity bar.

3. Look for Vega extension icon:

   

   Alternatively, navigate to Code > Settings > Extensions from the menu bar.

4. Enter "Kepler Studio" in the search field.

5. Select Uninstall.

6. Reload VS Code.

Reinstall the extension

1. Open VS Code.

2. Navigate to Settings > Extensions from the activity bar.

3. Look for Vega extension icon:

   

   Alternatively, navigate to Code > Settings > Extensions from the menu bar.

4. Enter "Kepler Studio" in the search field.
5. Click Install.
6. Click Reload if prompted.

Multiple app instances not supported

Cause: Metro packager can't support multiple simultaneous instances.

Solution: Stop the first app instance before starting a second one. Only one Vega app can run at a time.

Vega CLI commands fail without clear error information

Cause: Command execution errors that require detailed logging to diagnose.

Solution: Check log files at ~/.kepler/logs for detailed error information. Log files are named kepler_log_<timestamp>.log.

Related topics

• Set Up and Use Vega Studio
• Vega Studio Commands

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Last updated: Sep 30, 2025