comfyui-filename-prefix

Build filename_prefix from live workflow variables, or pick from saved presets

By laurigates·Created about a month ago·Updated 4 days ago· 1

laurigates/comfyui-filename-prefix

Nodes—

On cloudLocal install

Stars1

Updated4 days ago

Readme

comfyui-filename-prefix

Build filename_prefix from live workflow variables, or pick from saved presets.

Part of a family of mobile-first ComfyUI usability packs (gallery-loader, sampler-info): touch-friendly HTML modals that replace clunky native LiteGraph controls, detected by widget name, additive and non-clobbering.

Install

cd <ComfyUI>/custom_nodes
git clone https://github.com/laurigates/comfyui-filename-prefix
cd comfyui-filename-prefix
bun install
bun run build      # emit web/dist/ (served by ComfyUI)

Restart ComfyUI; hard-refresh the browser tab (Ctrl+Shift+R / Cmd+Shift+R).

What it does

Tapping a filename_prefix widget normally gives you a bare text box. ComfyUI supports a genuinely useful token syntax in that box — dated subfolders, values pulled straight out of your workflow's nodes — but nothing surfaces it, so most prefixes stay at whatever the workflow shipped with:

WanVideoWrapper_I2V        →  WanVideoWrapper_I2V_00042_.png

…and every run lands in one flat pile, indistinguishable from the last.

This pack replaces the text box with a builder:

Build — a palette of every variable the open workflow actually offers, read live from the graph. Tap wan-sampler-high › sampler to insert %wan-sampler-high.sampler%; the preview under the field shows the filename you'll actually get, resolved against current widget values:

renders/%date:yyyy-MM-dd%/%date:hhmmss%_%wan-sampler-high.sampler%_s%seed.seed%
    ↓
renders/2026-07-05/143052_euler_s123456_00001_.png

Presets — save a prefix you like and pick it in one tap on the next workflow. Presets are stored in ComfyUI's per-user settings, which live server-side, so the ones you save at the desktop are there on your phone.

It also catches the failure mode that makes these prefixes risky: rename a node and its token silently stops resolving, writing a literal %steps.value% into every filename from then on. Any token the open graph can't resolve is flagged before you apply it.

Widgets are matched by name and the enhancement is additive — the native control remains the fallback, and serialized workflows are untouched.

See docs/TOKENS.md for the full token reference, including which tokens are substituted by the frontend and which by the backend (the distinction explains most surprising behaviour).

Compatibility

ComfyUI: modern Vue frontend (comfyui-frontend-package >= 1.40) for the widget.onPointerDown interception hook.
Frontend changes take effect after bun run build + a browser hard-refresh — no ComfyUI restart.

License

MIT — see LICENSE.