Conciseness

The body is efficient — code carries the weight with brief rationale tables and no padding explaining known concepts — but "When to Activate" and "When to Use" are near-duplicate lists, and "Best Practices" restates the "Key Design Decisions" table. These are minor trimmable redundancies, matching anchor 4 rather than the fully lean anchor 5.

Actionability

Concrete, executable Python is given for hashing, cache storage, and the service-layer wrapper, including chunked hashing and corruption handling. It falls short of anchor 5 because serialize_entry(), deserialize_entry(), ExtractedDocument, and extract_text are referenced but never defined or stubbed, so the code is not fully copy-paste ready.

Workflow Clarity

The pattern is presented as a clearly sequenced four-part flow (hash → check cache → extract → store) with an explicit error-recovery checkpoint ("Treat corruption as cache miss" with try/except around cache reads). It is not a 5 because there are no broader validation steps (e.g., verifying a written cache entry or handling cache growth) and no explicit retry guidance beyond corruption.

Progressive Disclosure

No bundle files exist (references/, scripts/, assets/ are all absent), and the single SKILL.md is well-organized with clear section headers and a coherent overview-to-details flow. At ~155 inline lines it exceeds the under-50-lines simple-skill exception, and the full code listing could plausibly live in a scripts/ file, which keeps this at anchor 4 rather than 5.

Specificity

The description names one concrete action ("Cache expensive file processing results") with a specific mechanism ("using SHA-256 content hashes"), but does not enumerate several specific actions or file types (e.g., PDF, images) as the anchor-4/5 examples do. It sits clearly at "domain and 1-2 concrete actions, but not comprehensive."

Completeness

The "what" is clear and specific, but there is no "Use when..." clause or equivalent trigger guidance, which caps completeness at 3 per the judging guidelines. It is not a 2 because the "what" is concrete, not vague; it is not a 4 because the "when" is entirely missing rather than merely implicit.

Trigger Term Quality

"cache" and "file processing" are natural user terms, but "SHA-256 content hashes", "path-independent", "auto-invalidating", and "service layer separation" are technical jargon, and common variations like "memoize", "speed up reprocessing", or file extensions are absent. This matches "some relevant keywords but missing common variations or synonyms" rather than anchor 4's "good keyword coverage".

Distinctiveness Conflict Risk

Content-hash-based caching is a distinct technical niche ("SHA-256 content hashes", "path-independent, auto-invalidating") with a clear identity, giving minimal conflict risk with unrelated skills. It is not a 5 because the opening phrase "Cache expensive file processing results" could overlap with a more general caching/memoization skill.