RunningHub MiniMax H3 Legacy Unsupported Conditioning (Migration Error) (Legacy)

If you've opened a MiniMax H3 workflow and found a node that looks like RHMiniMaxH3UnsupportedConditioning sitting in the graph, you haven't found a feature - you've found a broken step, and the node is designed to tell you exactly that. It's a fail-closed placeholder: no matter what you do with it, running it raises an error on purpose. That's not a bug. That's the pack refusing to silently generate garbage from a workflow it no longer understands.

What it does

One input, task - fl2va or ref2va - and one output, conditioning. But the output is decorative. The node's only function is to throw an H3TaskNotImplementedError with instructions: delete this node and reconnect your graph to the correct modern encode node (MiniMaxH3FL2VAEncode for FL2VA, MiniMaxH3Ref2VAEncode for Ref2VA). The task dropdown exists purely so the error message can point you at the right replacement.

Why it exists

ComfyUI refuses to load workflows that reference node types it doesn't know - the dreaded "Node type not found" wall. When this pack reworked its conditioning pipeline and an old workflow referenced a conditioning construct that no longer exists, the author had two choices: let the graph break at load time with an unhelpful error, or register a placeholder node that loads fine and then fails loudly and helpfully at execution. They chose the second. So this node is a migration artifact, kept registered specifically so old serialized workflows still instantiate - and then immediately tell you what to fix.

What to do when you hit it

Delete it, first. Then look at what it was wired into and reconnect: if the task was fl2va, your old chain expected MiniMaxH3FL2VAEncode; if ref2va, MiniMaxH3Ref2VAEncode. If the whole workflow is older than the current node IDs, the pack's migrator is the easier route:

python3 tools/migrate_workflow.py old_workflow.json --in-place

It handles the MiniMaxH3* → RH* node-ID prefix changes, the split of a single vae_path into video_vae_path + audio_vae_path, widget-count drift, and stale combo options - reporting each substitution instead of silently picking something unselectable. And the genuinely modern answer for both tasks is RHMiniMaxH3VideoGen (text/keyframes) or RHMiniMaxH3RefGen (references), which absorb the encode steps entirely.

Install

Same as every node in the pack:

cd ComfyUI/custom_nodes
git clone https://github.com/RH-RunningHub/ComfyUI-RH-MiniMax-H3.git
pip install -r ComfyUI-RH-MiniMax-H3/requirements.txt

Restart, models in models/MiniMax-H3-INT8-CONVROT/ as usual. But really - the correct install for this node is the delete key. It's a signpost, not a destination.