visual studio code - Creating VSCode Debugger Extension -

i'm in process of trying write vscode extension support basic snes application development. have basic grammar definition , build task, have syntax highlighting, , able build project ctrl+shift+b using bass v14 assembler, i'm trying figure out how launch project using launch.json. i've worked through official docs , played around mock debugger project, can't seem figure out how adapt extension. start, i'm using bsnes-plus emulator debugger. there isn't command-line or ipc interface allow me implement proper debug adapter, want run program , pass output file launch. time being, i'm assuming bsnes-plus.exe located in $path, i'll try , figure out best practices external executable dependencies extension.

so here current questions:

• is "program" field of launch.json compiled application, or bsnes-plus.exe?
• if "program" application, specify bsnes-plus.exe? or vice versa.
• is there way specify own project-level variables, e.g. $output don't have hard-code output filename both build task , launch task?
• at 1 point, able launch command open bsnes-plus, not load game, , when closed it, vscode complained debugger terminated unexpectedly , re-opened bsnes-plus. how avoid this? need write debug adapter though it's not going do other launch application, can tell vscode exited cleanly?