Mpi To ChekPoint

Every generation in ComfyUI starts with the same trio: a MODEL, a CLIP, and a VAE. Wire-heavy workflows drag all three across the whole graph as separate connections, and that's the noodle-plate problem the pack's utility nodes keep nibbling at. MpiToChekPoint bundles the trio into a single MPI_CHECKPOINT wire, and its sibling MpiFromCheckpoint unpacks it back into the three sockets. One wire instead of three.

Yes, the class name is misspelled - MpiToChekPoint, no "c" in "check." It's the author's typo, baked into the node's identity, so search for it exactly like that or you'll think you have a missing node. The naming quirk is half of why people end up on this page.

The bundle is a pack-local type: a list that holds the model, clip, and VAE in order. MpiToCheckpoint takes the three required inputs (model, clip, vae, all forced-to-input) and emits mpi_checkpoint; MpiFromCheckpoint takes the bundle and hands back MODEL, CLIP, VAE in that same order. It's a mini context bus - the same bundling pattern the node-plumbing essay describes across rgthree's Context and the various pipe nodes, just scoped to the model trio instead of the whole graph state.

When it's worth it - and when it isn't

This earns its keep in graphs where the same model trio fans out to several consumers: multiple samplers, an upscale pass, a second stage. Bundle once after loading, unpack where each consumer needs the pieces, and the three-fat-wires-across-everything tangle thins out. The honest counterpoint, straight from the KB: a bundle hides which version of a value is inside. If you LoRA-patch the model after the bundle is made and unpack an earlier bundle downstream, you silently run base weights - the classic stale-context bug. Keep bundles short-lived and near their consumers, and don't bundle in the middle of a region where you're actively editing the model.

Install

Part of ComfyUi-MpiNodes. ComfyUI Manager (search "MpiNodes" / publisher "mad-pony-interactive"), or:

cd ComfyUI/custom_nodes
git clone https://github.com/MadPonyInteractive/ComfyUi-MpiNodes

Restart. No extra dependencies or model files.

What to know before you use it

MPI_CHECKPOINT is this pack's type - only MPI-aware nodes consume it, so the bundle's escape hatch is MpiFromCheckpoint, not any core node. Keep a From node around wherever the bundle ends, and remember the order is fixed: model, clip, vae, so the unpack is deterministic. And don't confuse it with saving a checkpoint to disk - this bundles objects in memory for routing, not a .safetensors file. If you want the latter, that's core's Save Checkpoint.