API reference and documentation of the system?

Is there API reference? And any documentation about the system?

I would like to inject faults on HTTP API level or method level, but I have not found any documentation.

No file, test, or entry point is named. Start by inspecting the repository structure and available notebooks or service entry points to determine whether an HTTP or method-level API exists. Done means providing API reference and system documentation that explains how fault injection can be performed.

Written by the indexing model from the issue text.