Skill

validate-vst3-editorhost

Tests VST3 plugin UIs (.vst3 bundles) in Steinberg's EditorHost without a DAW. Validates editor layouts, controls, resizing, and multiple instances visually.

testing

npx claudepluginhub iplug3/audio-plugin-dev-skills --plugin audio-plugin-validators

Tool Access

This skill uses the workspace's default tool permissions.

Preview

Minimal VST3 host for testing plugin UIs without a full DAW.

SKILL.md

Similar Skills

validate-vst3

Validates VST3 plugins (.vst3 bundles) using Steinberg's official validator tool on macOS, Windows, Linux. Guides usage, options, test suites, building from VST3 SDK, and common issues.

audio-plugin-validators

daw-music

Digital Audio Workstation usage, music composition, interactive music systems, and game audio implementation for immersive soundscapes.

3 files

custom-plugin-game-developer

ffmpeg-waveforms-visualization

Generates audio waveforms, spectrum analyzers, frequency bars, and vectorscopes using FFmpeg filters like showwaves, showspectrum. For music videos, podcasts, thumbnails.

ffmpeg-master

Stats

Parent Repo Stars55

Parent Repo Forks2

Last CommitFeb 10, 2026

Actions

View Source View Plugin View on GitHub View README

Help us improve

Share bugs, ideas, or general feedback.

VST3 EditorHost

Minimal VST3 host for testing plugin UIs without a full DAW.

Plugin Install Locations

editorhost accepts a direct path to a .vst3 bundle.

Platform	User Location	System Location
macOS	`~/Library/Audio/Plug-Ins/VST3/`	`/Library/Audio/Plug-Ins/VST3/`
Windows	`%LOCALAPPDATA%\Programs\Common\VST3\`	`C:\Program Files\Common Files\VST3\`
Linux	`~/.vst3/`	`/usr/lib/vst3/` or `/usr/local/lib/vst3/`

Instructions

Build EditorHost from the VST3 SDK if not already built (see Building EditorHost below)
Run: editorhost /path/to/plugin.vst3
The plugin UI window should appear — verify layout, controls, and resizing
Test multiple editor instances with --secondWindow
If the UI doesn't appear, verify the plugin passes validator tests first

Usage

# Basic usage - load plugin and show UI
editorhost /path/to/plugin.vst3

# With component handler (tests host callbacks)
editorhost --componentHandler /path/to/plugin.vst3

# Open second window (tests multiple editor instances)
editorhost --secondWindow /path/to/plugin.vst3

# Specify a particular effect class by UID
editorhost --uid "ABCD1234..." /path/to/plugin.vst3

Binary Locations

Platform	Typical Path
macOS	`<vst3sdk>/build/bin/Release/editorhost.app/Contents/MacOS/editorhost`
Windows	`<vst3sdk>\build\bin\Release\editorhost.exe`
Linux	`<vst3sdk>/build/bin/Release/editorhost`

Building EditorHost

Clone the VST3 SDK if you don't have it, then build:

cd <vst3sdk>
cmake -B build -G Ninja -DCMAKE_BUILD_TYPE=Release
cmake --build build --target editorhost

Linux: Requires X11 and GTK3 development libraries:

# Debian/Ubuntu
sudo apt install libx11-dev libgtkmm-3.0-dev libxcb-util-dev libxcb-cursor-dev libxcb-keysyms1-dev libxcb-xkb-dev

# Fedora
sudo dnf install libX11-devel gtkmm3.0-devel xcb-util-devel xcb-util-cursor-devel xcb-util-keysyms-devel libxkbcommon-x11-devel

Troubleshooting

Plugin doesn't load

Check the plugin path is correct
Verify the plugin passes validator tests first
Check logs: Console.app (macOS), Event Viewer (Windows), or stderr (Linux)

UI doesn't appear

The plugin might not have an editor (hasEditor() returns false)
Check if createEditor() is returning a valid view
Linux: Ensure X11 display is available (echo $DISPLAY)

UI appears but is blank/wrong size

Check defaultEditorSize() returns valid dimensions
For WebView UIs, check the HTML content is being set correctly
Try with --secondWindow to see if the issue is with first-time setup