Background JavaScript actions
Build focused textAction or fileAction plugins for transformations, APIs, file operations, and automation without requiring a custom window.
SwiftBiuX plugin system
Extend context actions with JavaScript or a full web interface
SwiftBiuX plugins can add fast background actions for text or files, while HTML + CSS + JavaScript web extensions can provide richer interactive interfaces. Plugins can participate in the toolbar, dedicated shortcuts, and other compatible trigger workflows.
Quick answer
Quick answer
SwiftBiu supports JavaScript plugins packaged as .swiftbiux extensions and richer HTML/CSS/JavaScript web extensions. Developers can build textAction or fileAction workflows, request only the permissions they need, and connect plugins to SwiftBiu triggers.
Verified 2026-08-12
What the plugin system supports
Interactive web extensions
Use HTML, CSS, and JavaScript when the workflow needs forms, previews, progress, editable results, or another custom interface.
Explicit permissions
Declare only the clipboard, file, network, notification, or host capabilities the plugin actually uses.
Useful plugin workflows
1
Create a custom selected-text action
Receive selected text, call your own processing logic or API, then copy or return the result to the user workflow.
- 1. Create a textAction manifest
- 2. Process selected text
- 3. Return or display the result
2
Build a fileAction plugin
Receive selected files, inspect the permitted paths, perform the declared file workflow, and save or report the output.
- 1. Create a fileAction
- 2. Request minimum file permissions
- 3. Process the selected files
3
Use a Web UI for interactive tools
Add a custom HTML interface when the user needs inputs, a preview, progress, editing, or a multi-step interaction instead of a one-shot background action.
- 1. Define the plugin
- 2. Add ui/index.html
- 3. Use the SwiftBiu web bridge
Installed extensions are visible and manageable in SwiftBiu
The macOS app includes an extension-management surface for built-in actions and installed SwiftBiuX packages, while the Developer Guide documents the manifest, permissions, APIs, Web UI bridge, debugging, and release flow.
Read the Extensions section in the guide →
What to know before building a plugin
- info Choose the smallest plugin type that fits the job: a background action for one-shot work, or a Web UI only when interaction is needed.
- info Plugins should declare only the permissions they actually use; file, clipboard, and network capabilities are explicit rather than assumed.
- info A plugin can participate only in input contexts and triggers that match its declared behavior and the host capabilities available to it.
SwiftBiu plugins FAQ
SwiftBiuX background plugins use JavaScript. Richer web extensions can use HTML, CSS, and JavaScript.
A textAction is designed around text input such as selected or OCR text, while a fileAction is designed around selected file input and the file permissions required by that workflow.
No. Many actions can run directly in background script.js. Add a Web UI only when the workflow needs user interaction, previews, forms, or editable results.
Yes. The SwiftBiuX template includes an AI Skill and quick-start guidance that helps choose the plugin type, permissions, manifest, script, optional Web UI, and packaging flow.
Go deeper
AI Quick Start
Generate a first installable plugin from a concrete workflow idea.
Plugin scenarios
Explore text, file, API, AI, and Web UI ideas.
Plugin Library
Browse the extensions and plugin entry points available on the website.
Text actions on Mac
See the selected-text context where textAction plugins can extend the action layer.
Turn your own workflow into a SwiftBiu action
Start with a focused textAction or fileAction, request only the permissions you need, and add a Web UI only when the workflow genuinely needs interaction.