Conciseness

The body is dense and command-heavy with no padding about concepts Claude already knows, but the core rule — final coverage belongs in pure_dart, not dart_minimal — is restated in the Overview, the Placement Gate, Phase 1 step 5, Phase 2 step 1, and twice in Common Mistakes, so noticeable tightening is possible. This matches 'mostly efficient but includes some unnecessary explanation or could be tightened' rather than anchor 4's 'minor instances'.

Actionability

Exact file paths (frb_example/pure_dart/rust/src/api/my_feature.rs), copy-pasteable ./frb_internal commands, a TwinNormal suffix mapping table, a fill-in PR reproduction template, and a mistakes-to-fixes table cover the common cases fully executable. Matches anchor 5.

Workflow Clarity

The two-phase workflow is rendered as an explicit decision graph with validation checkpoints ('Pass?', 'All tests pass?'), a Final Placement Gate checklist before PR preparation, and a feedback rule ('If any of these checks fail, return to Phase 2') — clear sequence, explicit validation, and error-recovery loops matching anchor 5.

Progressive Disclosure

No bundle files exist and the body is well-sectioned with clear headers and pointers to sibling skills, matching 'good structure; most content appropriately placed'. It is not 5 because at ~200 lines, content such as the architecture directory table and the reproduction-report template is inline where reference files would keep SKILL.md a leaner overview.

Specificity

The description names the domain (flutter_rust_bridge bug fix / feature development) but states no capability actions at all — the dart_minimal-then-pure_dart workflow the skill actually delivers is never mentioned, matching 'names the domain but actions are minimal or generic' rather than anchor 1 since the trigger contexts are concrete.

Completeness

The 'when' is explicit and detailed, but the 'what' is entirely absent — the skill's purpose must be inferred from context, which matches anchor 2 ('only when is present without what'). It is not 3 because no capability is even weakly stated.

Trigger Term Quality

'fixing bugs', 'adding regression tests', 'adding new features', and 'compilation is slow' are phrases a user would naturally say, giving good keyword coverage; a few natural terms are missing ('twin test naming conventions' leans jargon, and no synonyms like 'slow build' or 'tests' appear), so it falls just under the comprehensive anchor 5.

Distinctiveness Conflict Risk

The 'in flutter_rust_bridge' qualifier carves out a clear niche with minimal conflict against unrelated skills, but the broad triggers 'fixing bugs' and 'adding new features' overlap with closely related sibling skills (frb-test, frb-code-generation), matching 'mostly distinct; minor overlap risk'.