Conciseness

The body is short with no concept over-explanation, but several tokens do not earn their place: the "Do not use this skill when" bullets ("The task is unrelated to stride analysis patterns", "You need a different domain or tool outside this scope") are vacuous filler, and "Clarify goals, constraints, and required inputs" is generic boilerplate. This fits the 'mostly efficient but includes some unnecessary content that could be tightened' anchor rather than the lean score-5 anchor.

Actionability

The instructions are abstract to the point of emptiness — "Apply relevant best practices and validate outcomes" and "Provide actionable steps and verification" give no STRIDE-specific technique (no trust boundaries, no per-category elicitation prompts, no output template), matching the score-1/2 boundary. It lands at 2 only because "If detailed examples are required, open resources/implementation-playbook.md" is a (broken) pointer to where specifics would live, making it minimal high-level guidance rather than pure description.

Workflow Clarity

"Clarify goals... Apply relevant best practices and validate outcomes... Provide actionable steps and verification" implies a rough clarify-apply-report sequence, but the steps are poorly defined, there are no validation checkpoints, and nothing describes how to actually run a threat modeling session. This matches the score-2 anchor (rough sequence, many gaps, validation absent) rather than the listed-steps score-3 anchor.

Progressive Disclosure

The body delegates all detailed content to `resources/implementation-playbook.md`, but no such file exists anywhere in the bundle (no references/, scripts/, assets/, or resources/ directories), so the only route to substantive content is a dangling pointer. Scoring against the actual bundle structure, this is minimal structure whose reference is broken, fitting the score-2 anchor rather than the score-3 anchor where references are present and functional but unclear.

Specificity

"Apply STRIDE methodology to systematically identify threats" names the domain and one action (identify threats via STRIDE), but does not enumerate several concrete capabilities, matching the 'names domain and 1-2 concrete actions, not comprehensive' anchor. It is more informative than the score-2 anchor ('Processes PDF files') but falls short of the score-4 anchor's list of several specific actions.

Completeness

Both parts are explicitly present: the 'what' ("Apply STRIDE methodology to systematically identify threats") and the 'when' ("Use when analyzing system security, conducting threat modeling sessions, or creating security documentation"). The 'when' lists concrete triggers, but the 'what' stays at one high-level action without specifics, matching the score-4 anchor ('when' present, 'what' could be more explicit) rather than the fully concrete score-5 example.

Trigger Term Quality

Natural trigger phrases like "analyzing system security", "conducting threat modeling sessions", and "creating security documentation" give good keyword coverage a user would actually say. A few natural synonyms (e.g., risk assessment, security review, attack surface) are missing, so it fits the score-4 rather than the score-5 comprehensive anchor.

Distinctiveness Conflict Risk

"STRIDE methodology" carves out a clear niche with distinct triggers (threat modeling sessions, threat documentation), so it is mostly distinguishable. There is minor overlap risk with closely related skills like general security review or code review, fitting the score-4 rather than the minimal-conflict score-5 anchor.