Function resolve_spawn_args 

pub fn resolve_spawn_args(
    path: &str,
    task: Option<&str>,
    stdin_is_terminal: &dyn Fn() -> bool,
    model: Option<String>,
    workdir: &str,
    yolo: bool,
    allow: Vec<String>,
    max_depth: Option<usize>,
    regions: HashMap<String, String>,
    no_seed_commands: bool,
) -> Result<SpawnArgs>

Resolve the local inputs of a spawn request: find and parse the manifest, resolve the --<region> flags, resolve the task, and mint a run id from the agent’s directory name.

task is what --task was given, if anything. Left off, resolve_task opens the user’s editor, which is why stdin_is_terminal is threaded through: the probe itself is real I/O and belongs to the binary, so callers inject it (tests pass a fn that always says no).

Regions are resolved before the task on purpose. A typo’d --foo has to fail before the user is dropped into an editor and types a paragraph they are about to lose.