Shima VAE Pass

Shima VAE Pass is the most honest node in this pack: a VAE goes in, the same VAE comes out, and nothing happens in between. It's one of Shima's "Passer" family (Image Pass, Latent Pass, Model Pass, and friends), and if you've ever wondered why anyone would install a node that does literally nothing, the Passer family is the answer.

What a passer is actually for

The Shima docs explain it better than the node itself does: passers have optional inputs, and that optionality exists to stop ComfyUI's auto-wiring from incorrectly filling required inputs with mismatched types. When you drop an island onto the canvas and Shima's auto-link kicks in (via Use Everywhere / cg-use-everywhere), the broadcast system looks for compatible inputs to connect to. A passer at the edge of an island gives those broadcasts a valid, type-correct landing pad - a "stable airport," in the docs' metaphor - without forcing a hard connection. It also works as a protective plug: an optional VAE input that swallows a broadcast and passes it onward.

So you reach for VAE Pass when:

• You're building or extending a Shima island and want a VAE signal to enter the island cleanly at a defined boundary
• A Use Everywhere VAE broadcast needs a scoped landing point inside a group
• You want to make a required VAE socket effectively optional by inserting a passer with nothing feeding it

How it works

The mechanism is a single return statement. execute(vae=None) returns (vae,). That's it. The optional vae input defaults to None, so if nothing is connected - no broadcast, no wire - it outputs None rather than erroring. That's the entire point: it fails open instead of failing loud.

One thing worth knowing: it lives in the pack's legacy.py module, but it's still registered and searchable under Shima/Utilities/Passers, so don't let the "legacy" label scare you off. It's not deprecated, just old and stable.

Inputs and outputs

• vae (optional) - the VAE you're passing. Leave it unconnected and the node emits nothing
• vae (output) - the same VAE, unchanged

Output wires into any node that takes a VAE: samplers, VAEDecode, and so on.

Installing it

Part of the Shima pack (KDB-USJP/shima_wf). Via ComfyUI Manager, search "Shima" and install; or:

cd ComfyUI/custom_nodes
git clone https://github.com/KDB-USJP/shima_wf

Restart ComfyUI afterward. The pack's install.py clones cg-use-everywhere and ComfyUI-Impact-Pack if they're missing - cg-use-everywhere matters for this node because the whole passer concept assumes a broadcast bus exists to land on.

Gotchas

The one real trap: because the input is optional and defaults to None, you can wire VAE Pass into a required VAE input downstream and get a confusing "None is not a valid VAE" error if nothing is actually feeding the passer. The passer is not a fallback or a cache - it never conjures a VAE out of thin air. If downstream errors, check that something is genuinely connected upstream or that a Use Everywhere broadcast is matching. It's a pass-through, not a generator, and expecting more from it is the only way to be disappointed.