Debug Adapter Protocol
The Debug Adapter Protocol (DAP) defines the abstract protocol used between a development tool (e.g. IDE or editor) and a debugger.
VS Code showing inline values powered by the Python Debug Adapter
VS Code's multi-thread debugging powered by the Java Debug Adapter
REPL console in VS Code powered by the Node.js Debug Adapter
The protocol defines the format of the messages sent using JSON between the development tool and the debug adapter.
The DAP has been implemented for many debuggers or runtimes and some development tools are hosting these debug adapters.