auggie --version hangs (100% CPU) when ~/.claude/skills contains a large skill tree -- discovery runs even for --version #178

Environment

• auggie 0.36.0 (commit 7c61e5bb), installed via npm install -g @augmentcode/auggie
• Windows 11 Home 10.0.26200, Node v24.20.0
• Fresh install, not logged in, no ~/.auggie directory

Symptom

Every auggie invocation — including auggie --version — hangs indefinitely with one core saturated (~70% CPU) and produces no output.

Repro

1. Have a data-dense skill under ~/.claude/skills/: its references/ subtree contains ~40,000 directories and ~36,000 .md files (an EDB indicator dictionary exported as markdown; total entries under ~/.claude/skills: ~79,700).
2. Run auggie --version → hangs, no output ever.
3. Control experiment: point both CWD and USERPROFILE at an empty directory → auggie --version returns instantly (0.36.0 (commit 7c61e5bb)).

Diagnosis (via node --inspect + CDP)

Paused the hung process 5 s in and captured the JS stack:

hasFrontmatter            (frontmatter parse)
<recursive dir-walk fn>   x8 levels
...
registerDiscoveredCommands
registerCommands

The innermost frames were walking ~/.claude/skills/<data-heavy-skill>/references/.... CPU delta over a 5 s window while hung: ~3,438 ms — busy scanning, not blocked on I/O.

Root causes as I read them from the bundle:

1. Command/skill discovery runs unconditionally during CLI setup — even --version / --help pay for it before commander can answer.
2. The walk is fully synchronous (readdirSync + lstatSync per entry), recursive, with no entry cap or depth limit. It only skips entries whose name starts with ..
3. Every .md in the tree is read and frontmatter-parsed during discovery, so a skill that legitimately ships a large references/ data tree makes startup cost unbounded.
4. Symlinks/junctions are followed (only "plugin"-source scans skip them). On Windows, legacy compatibility junctions such as AppData\Local\Application Data point at their own parent directory — beyond the volume problem this is a potential infinite-recursion hazard.

Suggestions

• Short-circuit --version / --help before any discovery work.
• During discovery, parse command/skill candidates only at defined locations (skill root SKILL.md, commands/ directories) rather than every .md anywhere in the tree.
• Add an entry/depth cap, or move discovery off the startup critical path (lazy/async, cached).
• On Windows, skip entries with hidden/system attributes and avoid following junction cycles.