The description names the domain ('Allium specification') and a key action ('structured discovery session'), but doesn't list multiple concrete actions beyond 'build a specification through conversation.' It lacks specifics about what the session produces or what steps are involved.

Clearly answers both 'what' (run a structured discovery session to build an Allium specification through conversation) and 'when' (explicit 'Use when' clause with multiple trigger scenarios covering creating specs, gathering requirements, capturing behaviour, etc.).

Excellent coverage of natural trigger terms: 'create a new spec', 'elicit or gather requirements', 'capture domain behaviour', 'specify a feature or system', 'define what a system should do', 'describing functionality', 'shaping it into a specification'. These are terms users would naturally use when they need this skill.

The 'Allium specification' term provides some distinctiveness, but terms like 'gather requirements', 'specify a feature', and 'define what a system should do' could overlap with general requirements engineering or documentation skills. The Allium-specific framing helps but the broad trigger terms increase conflict risk.

The skill is well-structured and most content earns its place, but there's some verbosity in sections like the abstraction tests (Why test, Could it be different test, Template vs Instance test) that overlap conceptually. The tables and examples are helpful but could be tightened. Some explanations like 'The hardest part of specification is choosing what to include' are filler Claude doesn't need.

The skill provides highly concrete, actionable guidance: specific questions to ask at each phase, exact Allium syntax examples, redirect tables for common situations, concrete examples of good vs bad questioning, and clear session timing structure. The elicitation methodology phases give Claude a precise playbook to follow.

The four-phase elicitation methodology (Scope → Happy Path → Edge Cases → Refinement) is clearly sequenced with explicit outputs for each phase, specific 'watch for' checkpoints, and a concrete session structure with time allocations. The 'After elicitation' section provides clear handoff guidance to other agents. Each phase has validation through defined outputs.

The skill references two external files (language-reference.md and library-spec-signals.md) which is appropriate, but the main body is quite long (~300+ lines) with sections like the abstraction tests and common traps that could potentially be split into reference files. The structure within the file is well-organized with clear headers, but the monolithic nature works against quick scanning. No bundle files were provided to verify reference accuracy.