/pkl convert

Migration tool. Dumps any loaded JSON resource, vanilla or modded, as PKL into config/pkl4mc/data/<namespace>/<path>.pkl:

/pkl convert minecraft:recipes/stick
/pkl convert minecraft:loot_tables/chests/ancient_city
/pkl convert nothingcore:cooked_sea_pickle

The argument is a resource location. .json is appended automatically if missing. The written file lands in your data directory, where it immediately overrides the original. Edit from there.

Converting is a good starting point when porting an existing datapack: convert, then refactor toward the schemas for typing and autocomplete. The converter produces a literal translation, not schema-based files.