quantize_nbits was added to the Core ML Converter node's required INPUT_TYPES,
so ComfyUI's /prompt validation rejected (HTTP 400) any workflow saved before
Phase 6 — the field is absent from those prompts. The Tier 2 golden-image test
caught this. Move it to optional: omitted inputs fall back to the convert()
default of "none", so old workflows validate and behave identically while new
users can still opt in. Restores the Gate 6 'existing workflows unaffected'
guarantee.
aszc-dev
6a0ccbeb60