MiniMax H3 Easy Segment Step

MiniMax H3 Easy Segment Step is the workhorse of the pack's per-segment control workflow, and it exists to fix a genuinely annoying problem: rerunning a long H3 video costs you everything when only one shot is wrong. H3 chains segments to build longer clips than a single generation allows, passing continuity from one shot to the next. The pack's one-node path (MiniMax H3 Easy Segment Sample) handles that fine, but it re-executes every segment on every queue. A chain of Segment Steps changes that - each Step samples exactly one shot, with its own seed, and ComfyUI can cache the ones that didn't change.

So when you have a five-shot video where shot 3 came out stiff and you only want to regenerate shot 3 onward, the Step chain is what you build instead of the single Sample node.

How it works

Each Step resolves which shot it owns from its position in the chain, not from any number you type: the first Step has sample_setup connected and is shot 1; every later Step wires only Previous segment, and its index is simply the previous Step's index plus one. The node pulls that shot's prompt and @-referenced media from the plan, rebuilds that segment's own conditioning, applies whichever continuity mode the Context Segments node chose - latent guide handoff, multi-frame RGB guide, or a soft/hard AV prefix that carries overlapping audio - then runs the actual sampler over that shot's latent. The sample it returns carries its own head, delivery, and output frame counts plus the full accumulated chain state.

Two details make it behave differently from the one-node path. First, caching: the node's change detection is keyed on (seed, prompt_override), so an unchanged early Step hits ComfyUI's native cache and only the changed segment and its successors resample. Second, the optional prompt_override: connect a STRING to replace just this shot's prompt while the rest of the chain keeps its Context Segments prompt.

The inputs and outputs that matter

• seed (required, 0 to 4294967295, with control_after_generate) - this Step's independent seed. Change it to re-roll this shot.
• previous_segment (optional) - the previous Step's output, on every Step after the first.
• sample_setup (optional) - the MiniMax H3 Easy Sample Setup output, on the first Step only.
• prompt_override (optional) - an external STRING to replace just this shot's prompt.
• Output: segment, which feeds either the next Step's previous_segment or - for the final Step - Segment Collect.

Chain shape:

Sample Setup → Step 1 ─previous→ Step 2 ─previous→ Step 3 → Collect → Decode
   (own seed)     (own seed)           (own seed)

Installing it

Ships in the ComfyUI-MiniMaxH3-Easy pack:

cd ComfyUI/custom_nodes
git clone https://github.com/nkxx188/ComfyUI-MiniMaxH3-Easy.git

Restart ComfyUI. Via ComfyUI Manager search the pack title and install the Nightly version - the stable releases can lag the repository. Recent ComfyUI with the official MiniMax H3 nodes and the H3 model files in ComfyUI/models are prerequisites for the whole suite.

Common issues

A few traps, mostly self-inflicted. A prompt_override must contain exactly one segment - no --- dividers - and if you override the prompt you also take over its media references: the pack's rule is that a segment only uses images, videos, or audio explicitly @-referenced inside its own prompt, and nothing is inherited from the previous shot, so include your own @Image1-style mentions in the override. Connecting sample_setup to anything but the first Step errors on purpose. Build more Steps than the plan has shots and you'll get an explicit "chain contains more steps than Context Segments" error. And if your steps come from different Context plans, the chain validation stops you cold. Keep the first run doing the whole video, then lean on the cache: change only the seed or prompt of the segment you actually want re-rolled.