MiniMax H3 Upscale Reference + Prompt Override

Here's a problem the Contex Loop pack solves that you might not have realized you had: when you upscale a completed scene (or a whole checkpointed branch) through the deferred upscale loop, that second pass runs without your original reference wires connected. The pack handles it by caching each active scene's native reference latents and compact Qwen presentation, keyed to the checkpoint fingerprint, and restoring them automatically. That's elegant - until you look at a 2K result and think "great, but I'd reword that prompt for the upscale, and I want a different reference face."

MiniMax H3 Upscale Reference + Prompt Override is the escape hatch. It sits inline on your normal H3 Tagged Reference chain - so it changes nothing about generation - and only tells the deferred upscale loop what to use instead. Connected refs replace the automatic cached payload; an unconnected references socket means "leave automatic cache restore alone." You get pass-2 control without forking your whole production graph.

What you set

• prompt_override - optional pass-2 prompt. Blank means Upscale Reference Conditioning reuses the exact compiled source-scene prompt. Fill it in and the upscale pass is re-prompted; this is where you add "sharpening-friendly" or cleanup phrasing without re-rolling the base render.
• disabled_tags - comma-separated @tags to strip from the connected pass-2 registry. If a motion reference made the base render great but the upscale drift-prone, drop its tag here. Leave blank to preserve the reference line exactly. One catch: the node validates the list, so an unknown tag raises an error rather than silently doing nothing.
• references - optional. The normal Tagged Picture/Video/Audio Ref line. When connected, this explicit registry replaces the automatic cached refs for pass 2.

Outputs: references (the same line, optionally filtered by disabled_tags), prompt_override (the pass-2 prompt string, blank when preserving the source), reference_fingerprint (of the effective connected registry, blank if nothing was connected), and status (whether the node passed, filtered, or omitted refs - check it if you're unsure which branch you're on).

How it slots in

Upstream on the chain you'll have the Tagged reference nodes feeding this override's references; downstream, the resulting line goes into the upscale reference conditioning (the standalone deferred loop that takes a selected-manifest output with no source Plan). On the Tagged Ref2VA side, cache_for_upscale is what seeded the automatic cache in the first place - turn that off and the override becomes the only way pass 2 gets references, which is a deliberate pattern for people who want the upscale to re-read from explicit wires every time.

The honest sizing: this is a finisher's node, not a beginner's. If you're still getting your first multi-scene renders out, you can ignore it entirely - the cache-restore default works. Reach for it when you're doing SeedVR2-style whole-chain finishing and you want the second pass to see different text or different refs than the first pass used.

Install

Part of the Contex Loop pack:

cd ComfyUI/custom_nodes
git clone https://github.com/ethanfel/ComfyUI-MiniMaxH3-Contex-Loop.git

Restart ComfyUI (or Manager → "MiniMax H3 Contex Loop"). No models bundled - H3 weights plus video and audio VAEs, and a current ComfyUI build with native Add Guide for MiniMax H3 (PR #15439). ffmpeg on PATH preferred for review/assembly; PyAV fallback. Pack is GPL-3.0; the H3 weights are territory-restricted (no US/EU/UK/South Korea, outputs included). And keep in mind: upscaling doesn't fix a prompt you're embarrassed about - it re-renders it, and this node is where you say so.