v4 could not remove a built-in node from the pipeline and the reason was
structural: the wiring lived in code as a CORE dict nobody could reach, so
"remove this" had nothing to delete and "use a different one" had nothing to
change. Code is not a thing a user can edit.
The pipeline is now data. Three operations over it, each refusing with a
reason rather than half-doing the job:
build turns slots into the prompt ComfyUI queues, checking every link's type
and refusing a graph that cannot work. replace points a slot at any node
producing what its consumers read -- the built-in ones have no special
standing, which is what makes them replaceable rather than merely present.
remove takes a slot out and rewires what it fed to what fed it, when the
node has exactly one input matching each CONSUMED output; v4 required one
for every output a class could produce, so a spare FLOAT nobody wired made a
node unremovable.
Demonstrated against real schemas: FunPack's VAE loader swapped for core's
VAELoader, the modifiers node removed with the sampler rewired to read the
model directly, and removing the empty latent refused because nothing
upstream could feed what it fed.
Then run for real. The default pipeline, with three loader slots replaced by
one checkpoint slot, built from data, accepted by ComfyUI's own
validate_prompt, and executed by its own engine to execution_success and a
picture. Every wiring and type validated on the first attempt; the only
things ComfyUI objected to in the untouched default were the three unset
file pickers, which is correct -- a fresh install cannot know which model
you own.
Added a checkpoint loader, because the split loaders are right for LTX and
H3 and cannot read an SD-family single file at all.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
