Conciseness

Individual sections are terse, but the body carries generic template filler Claude already knows — 'Optimize for clear, verifiable outcomes with the minimum necessary changes', 'Redact secrets, tokens, credentials' — plus a Table of Contents for a short document. This is more than the 'minor instances of over-explanation' of anchor 4, but the body is not severely padded either, so it sits at anchor 3.

Actionability

One executable, complete code example exists (PortParser.parse/1), but the core OTP guidance — 'Model long-lived state with GenServer', 'Let supervisors restart failed workers' — has no concrete code, command, or module skeleton. Guidance is real but incomplete relative to the skill's stated scope, matching anchor 3 rather than anchor 4's 'concrete code or commands with minor gaps'.

Workflow Clarity

The Procedure section gives a clear 3-step sequence (confirm scope → focused changes → re-run validations) and the Validation section adds explicit checkpoints ('Fail fast: stop at the first blocking validation failure', 'Re-run checks after fixes'), i.e., a feedback loop. The gap keeping it below anchor 5 is that validations are named abstractly ('highest-signal validations', 'relevant local checks') with no concrete commands.

Progressive Disclosure

The deep-guidance reference is well-signaled with a read-when condition, but the path given is wrong: the body says 'Infrastructure/references/deep-guidance.md' while the actual bundle file is 'references/deep-guidance.md' — following the written path fails. The Table of Contents also omits roughly half the body's sections (Philosophy, Procedure, Validation, Constraints, Anti-patterns, References). These are more than 'minor organization gaps' of anchor 4, but structure and signaling intent are present, placing it above anchor 2.

Specificity

The description names the domain ('idiomatic Elixir code with OTP patterns, supervision trees, and Phoenix LiveView') and exactly two concrete actions — 'Create and review' — matching the anchor for 1-2 concrete actions but not comprehensive. It does not list several distinct actions (no debugging-specific actions, no review dimensions), so it falls below anchor 4.

Completeness

It clearly answers both questions: 'what' is 'Create and review idiomatic Elixir code with OTP patterns, supervision trees, and Phoenix LiveView' and 'when' is the explicit trigger clause 'Use when building or debugging Elixir services that need reliable concurrency and fault tolerance', with concrete trigger phrases. Not the lower anchor 4, since the 'when' clause is explicit and specific rather than merely present.

Trigger Term Quality

Good natural keyword coverage: 'Elixir', 'OTP', 'supervision trees', 'Phoenix LiveView', 'debugging', 'concurrency', 'fault tolerance' — terms users would naturally say. A few natural terms are missing (e.g., 'mix', '.ex', 'Erlang', 'BEAM'), so it does not reach comprehensive anchor 5.

Distinctiveness Conflict Risk

A clear niche (Elixir/OTP/Phoenix LiveView) with distinct, unambiguous triggers ('building or debugging Elixir services'); minimal risk of triggering for the wrong skill. Not lower anchors, which require overlap with generic or closely-related skills.