> For clean Markdown content of this page, append .md to this URL. For the complete documentation index, see https://buildwithfern.com/learn/llms.txt. ## 0.31.2 **`(internal):`** Add an `internal` package, which now contains the internal functionality previously included in the `core` package (e.g. `core.Caller` -> `internal.Caller`). Although technically a breaking change in terms of the module itself, this change was always the intention, and should have zero impact on users. Any `core` type that is meant for public consumption remains in the exported `core` package (e.g. `core.APIError` and `core.RequestOption`). ## 0.31.1 **`(internal):`** Adds additional tests to confirm the behavior of the `core.Retrier`. No functional, user-facing changes are included.