Clayworks's (uncolored) Glazed Terracotta block could be made compatible with modpacks and mods that add recipes and interactions involving Glazed Terracotta by tagging Glazed Terracotta with the #minecraft:glazed_terracotta tag. This way, any mod that invokes the glazed terracotta tag item would automatically include Clayworks's Glazed Terracotta, with no additional work needed by mod and modpack developers to add compatiblity.

Neither #minecraft:glazed_terracotta or forge:glazed_terracotta seem to exist