Lumi Seed

Lumi Seed is the simplest honest node in the pack: one integer in, one integer out, plus the control_after_generate menu - randomize, increment, decrement, fixed - that ComfyUI shows on every KSampler seed widget. Its whole job is to be a seed source you can wire into several nodes at once, so one seed drives your whole workflow instead of you juggling five widgets.

Why would you want that instead of just using the seed widget on each node? Because "change one variable at a time with a fixed seed" is still the core discipline of this hobby - the community advice that shows up in every thread about comparing settings. A single Lumi Seed feeding your sampler, your noise, and your wildcard node means one bump changes everything coherently, and locking it lets you iterate on one parameter without the noise. It's the same niche rgthree's Seed node occupies in bigger packs: a small node that makes workflow-wide seeds manageable.

The input and output

• seed - the value, 0 to 4,294,967,295 (the standard 32-bit ComfyUI seed range), default 0. The dropdown next to it is control_after_generate: pick randomize and every queue run advances the seed; pick increment or decrement and it steps; fixed keeps it frozen.
• Output: seed, a plain INT. Wire it into anything with an INT seed input - KSampler, Lumi Noise To Seed's cousins, the shuffle and wildcard nodes, even the LLM processors.

It's a passthrough - no randomization logic hidden in the node itself; the widget does all the work, and the node faithfully reports what it holds.

Installing

cd ComfyUI/custom_nodes
git clone https://github.com/illuminatianon/comfyui-lumi-tools
cd comfyui-lumi-tools
uv sync

Restart ComfyUI, or pick up "Lumi Tools" in ComfyUI Manager. No dependencies to worry about beyond the pack's two standard ones.

Where it's a trap and where it's a win

The trap is thinking a shared seed means shared outputs. It doesn't - a single seed doesn't synchronize the random state of unrelated nodes; it just means the value you control is common. The win is the workflow you keep returning to: set it to randomize, hit queue, and every node gets a fresh coordinated value each run; then when you find a composition you like, flip to fixed and preserve it while you tune the prompt. If you only ever use one seed widget in a workflow, this node is pointless for you - skip it. If you have a graph with a sampler, a wildcard, and an LLM pass that all need to stay in lockstep, it's the one small node that keeps you sane.