This package provides the Stan code for the mpt2irt package and is most likely only useful in combination with mpt2irt.
You can install mpt2irtStan from GitHub with:
# install.packages("remotes")
remotes::install_github("hplieninger/mpt2irtStan")
For further information regarding installation and usage of this package in combination with mpt2irt, see mpt2irt.