TL schema and RPC calls

KPHP has lots of features related to TL schema — because historically it was used only as an RPC client.

TL/RPC is also used as a transfer layer between microservices written with KPHP: services are launched as RPC servers, and all available requests are described with TL schema.
If you don’t plan to use KPHP microservices and you don’t have any RPC servers, probably skip this chapter.