The two libraries out there that I found seem to be hand-rolled - Box.net have an official OpenAPI descriptor at https://github.com/box/box-openapi https://git

The two libraries out there that I found seem to be hand-rolled - Box.net have an official OpenAPI descriptor at https://github.com/box/box-openapi https://github.com/box/box-openapi , that you can one-time feed into an OpenAPI-to-PHP codegenerator such as https://github.com/janephp/open-api https://github.com/janephp/open-api or https://openapi-generator.tech/ https://openapi-generator.tech/ to produce a PHP SDK. This should help address the "relatively unmaintained" part, but the disjointedness is perhaps going to rely heavily on how idiomatic the generated code looks (and you will almost certainly want to ensure there is low-memory/streaming support for file upload/download APIs).