Fix Root Causes

Portability (required)

This skill is part of the portable pstack pack.

1. Read the pstack capability contract and the adapter for the active coding agent before any helper delegation.
2. Prefer capability verbs (explore, implement, review, parallel, ask_user, verify, model_role) over vendor tool names.
3. Resolve models through model_role. Never require a vendor-specific model identifier.
4. When helper spawning is unavailable, run the work on the lead agent and state that fan-out was collapsed.

When debugging, do not paper over symptoms. Trace every problem to its root cause and fix it there.

Why: Symptom fixes accumulate. Each workaround makes the system harder to reason about, and the real bug remains. Root-cause fixes are slower upfront but reduce total debugging time.