Looking through ?options I see documentation of options in base R as well as a few default packages like utils and graphics. However, any R contributor can create packages that define some options, but it seems like documentation for these options cannot be found.

1. How can one identify options that are referenced by a loaded package?
2. How should package "options" be documented in R packages if there is any documentation at all? I guess there is no way to append the special options for your package to the base ?options Rd file.

As an example, the package RBesT does some Gibbs sampling with the stan package, and one can set the simulation parameters as options with some endemic handles. (The documentation for the package dataset crohn covers this, otherwise I wouldn't have been aware of their existence).