| name | decky-preview |
| description | Drive the Decky Plugin Studio in-IDE preview for fast iteration. Use when developing UI/focus behavior, testing hardware simulator scenarios, or verifying state preservation across HMR. Covers preview.start/stop/status, preview.injectFocusEvent, preview.setHardware, preview.runSequence, preview.callRpc, and preview.readLog MCP tools. |
Decky preview (Decky Plugin Studio)
Very much beta — fast UI/RPC iteration only. Focus, layout, and Steam Input need deck.deploy + on-device QA.
When to use
- Iterating on
@decky/ui components without full build/deploy/Steam loop
- Verifying D-pad focus paths after refactors
- Testing plugins that read hardware telemetry or call local Ollama
- Scripted regression via
preview.runSequence
Input paths
Manual focus testing (all post into the same decky-focus bridge):
- Keyboard — arrows, Enter (A), Escape (B) while preview panel focused
- Virtual gamepad — on-screen buttons in the preview panel
- Physical controller — connect Xbox/DirectInput pad; enable Use physical controller; keep preview panel focused
MCP preview.injectFocusEvent and preview.runSequence reach the live preview when Decky: Open Preview is running (IPC via ~/.decky-plugin-studio/preview-ipc/).
Workflow
- Start preview —
preview.start or VSIX command Decky: Open Preview
- Check status —
preview.status returns running state, preview URL, hwState
- Simulate hardware —
preview.setHardware({ cpuTemp: 85, battery: 8, preset: "Hot Game" })
- Drive focus — physical D-pad, keyboard, virtual pad,
preview.injectFocusEvent("Right"), or preview.runSequence({ inputs: ["Right","Down","A"], delayMs: 80, snapshot: "dom" }) (requires preview open)
- Backend RPC —
preview.callRpc("method_name", [arg1, arg2])
- Logs —
preview.readLog({ lines: 50 })
runSequence result fields
focusPath — ordered list of focus callbacks firedactiveElement — selector chain for final focusdomSnapshot — serialized QAM frame HTML (trimmed)logTail — recent plugin.log lines during the sequence
Limitations
Preview mocks @decky/api and @decky/ui. Physical gamepad requires a user gesture in the preview webview (press any button after focusing the panel). Steam Input chord actions are not mapped. Tricky CEF focus bugs still need on-device QA via deck.deploy and the decky-debugger persona.
