LorenEteval_Furious/Furious/Backends/ExternalCore/AGENTS.md

External Core backend guidance

Configuration contract

• External Core is protocol-agnostic. Keep executable path, working directory, argument vector, environment mapping, proxy endpoints, shutdown timeout, and application-tun2socks choice as distinct fields.
• The editor projects these known fields but must preserve unknown top-level fields. Loading is observational and an untouched save must not normalize paths, arguments, environment variables, or future fields.
• Execute with shell=False. Never concatenate arguments into a shell command or log credentials/environment secrets.

Runtime and TUN ownership

• Own the exact Popen instance and its reader/watcher resources. Startup failure and shutdown must close callbacks, terminate, kill if necessary, and reap the exact child within configured bounds.
• Application tun2socks is explicit and requires a valid remote address. This backend does not inject a native core TUN block or infer protocol-specific behavior.
• Validation dialogs are transient asynchronous UI: use the established open() ownership path and release them on destruction without retaining them in backend or plugin registries.

Code review and verification

• Flag shell execution, ambiguous string arguments, inherited transient callbacks, unknown-field loss, and unbounded child-process cleanup.
• Use fully mocked subprocess and host-network operations. Test mapping round trips, unknown-field preservation, validation failures, output-reader shutdown, tun2socks validation, and repeated editor/dialog destruction.