Function resolve_command 

pub fn resolve_command(command: &str) -> Result<PathBuf>

Resolve command to an absolute path on disk.

• If command is already absolute or contains a path separator, canonicalize it (resolves symlinks).
• Otherwise consult augmented_path_var (and try a .exe suffix on Windows). Returns the first match found, canonicalized.

Resolving against the AUGMENTED PATH — not the raw ambient one — is what keeps install-time and runtime agreeing. mur agent mcp add / addon import run under whatever PATH their parent had: a terminal has ~/.local/bin, a Hub-spawned sidecar does not. The runtime always spawns against augmented_path_var, so a raw-PATH resolve here made command: uvx installable from a shell and “could not find uvx on PATH” from the Hub — the same entry, two answers. Ambient entries still keep priority, so this only ever finds MORE binaries, never a different one.

Returns an error if the binary can’t be located.