MiniMaxH3LatentLabSeededDisableNoise

This is a small node with a surprisingly specific reason to exist. In a two-stage H3 run - a main pass followed by a refine or continuation pass - you often want the second stage to add no fresh noise at all, because the first stage already owns the creative direction. Stock ComfyUI has a DisableNoise node for exactly that. The problem: it hardcodes seed = 0. And as the LongMedia source code points out, SamplerCustomAdvanced forwards the NOISE object's seed into guider.sample(), so a seed-0 noise carrier quietly resets your whole trajectory even though it's not adding noise.

MiniMaxH3LatentLabSeededDisableNoise is the same trick with the seed carried through. You give it one seed (INT, default 0), and it hands you a NOISE object that produces zero noise - it generates empty noise via ComfyUI's prepare_empty_noise - but tags it with the seed you passed. The second stage stays deterministic and reproducible instead of silently resampling from a different point.

Where it fits

You'll find this inside LongMedia's continuation machinery: when a segment is re-sampled as continuation context, the runtime wants "no fresh noise" semantics while keeping the pipeline's effective seed intact. That's the whole job. It lives in the MiniMax H3/LongMedia/Internal category, and like most of this pack's internal helpers, you usually won't add it by searching - it gets dropped in by a saved workflow or a workflow you're porting from an earlier LatentLab-era graph. If you can't find it in the Add Node menu, that's normal, not a missing install.

For manual A/B testing you can wire it into a sampler's noise input the way you'd wire stock DisableNoise, with the bonus that your seed actually survives.

Install

It ships in one pack, and installing the pack is all there is to it - there are no extra pip dependencies (the project declares none):

cd ComfyUI/custom_nodes
git clone https://github.com/vizart-vj/ComfyUI-MiniMax-H3-LongMedia

Restart ComfyUI. You can also use ComfyUI Manager and search for "MiniMax H3 LongMedia". The heavy lifting - the actual MiniMax H3 checkpoint, its video and audio VAEs, and the CLIP model - lives in ComfyUI's standard model folders, not in this pack, so you need those downloaded via ComfyUI's native H3 support before any of this does anything useful.

Gotchas

• It's a zero-noise carrier by design. If you expected fresh, seeded noise, this is the wrong node - that's what stock KSampler/RandomNoise is for.
• Remember the H3 weights themselves are license-locked out of the US, EU, UK and South Korea (the MiniMax H3 Community License), which is a legal check that applies to the whole pack, not just this node.

One input, one output, one job. It's the quiet fix that stops your long-form H3 runs from drifting between passes, and knowing it exists will save you an hour of wondering why a "no noise" second pass keeps landing somewhere else.