Conciseness

The body is short overall, but it spends tokens on things Claude already knows: the opening paragraph explains why cross-browser testing matters ("each with unique rendering engines... broken layouts, missing features"), and an entire 'Explain' section directs Claude to justify the importance of browser testing. This fits anchor 3 ('mostly efficient but includes some unnecessary explanation') — not 2, since the Quick Reference bullets and Code Review section do carry real instruction, and not 4, because two sections are pure padding that could be cut.

Actionability

The Quick Reference bullets give some concrete guidance ("Test on Chrome, Firefox, Safari, and Edge at minimum", "Use automated tools like Playwright or BrowserStack", "Check CSS features with caniuse.com"), but the Check/Fix sections are abstract ("Verify that this website works correctly", "Fix browser-specific issues") and no executable commands or code live in the body — they are all deferred to references/rule.md. This matches anchor 3 ('some concrete guidance but incomplete; missing key details') rather than 4, where the body itself would carry mostly executable instruction.

Workflow Clarity

The Check → Fix → Explain → Code Review sections provide a recognizable phase order, but there are no validation checkpoints or feedback loops (e.g., 'run the CI workflow and confirm it fails on an unsupported browser'), matching anchor 3 ('steps listed but validation gaps; checkpoints missing or implicit'). It does not reach 4 because nothing tells Claude how to verify a finding before flagging it, and it stays above 2 because the Code Review section does state a clear, specific output ('Flag exact gaps where the rule is not automatically verified or where failures do not block regressions').

Progressive Disclosure

The body is a concise overview and correctly pushes implementation detail to one real, one-level-deep bundle file ("see `references/rule.md`", which exists and contains the promised code examples, CI workflow, and tool guidance). It is not 5 because the pointer sits alone after a horizontal rule as plain text rather than a labeled link, and the inlined Quick Reference partially duplicates the reference file's checklist content instead of navigating to it — matching 'good structure; references mostly clear; minor organization gaps'.

Specificity

The description names the domain ("Test across all major browsers") and one concrete reviewing action ("reviewing CI coverage, automated checks, or test strategy"), which matches the '1-2 concrete actions, but not comprehensive' anchor. It does not reach 4 because it never lists the skill's actual capabilities (e.g., audit CI workflows, flag unverified rules, check Playwright/BrowserStack configs); it stays above 2 because the actions go beyond a bare domain mention.

Completeness

Both parts are present: an explicit 'when' ("Use when reviewing CI coverage, automated checks, or test strategy...") and a 'what' ("reviewing... Focus on whether the rule is continuously verified, not just documented"). It is not 5 because the 'what' is thin and folded into the trigger clause rather than stating the skill's concrete outputs, and not 3 because the 'Use when' trigger is explicit rather than weakly implied.

Trigger Term Quality

Relevant keywords are present ("CI coverage", "automated checks", "test strategy", "browsers") but common natural variations are missing: users would say "cross-browser testing", "browser compatibility", "works in Safari/Chrome/Firefox", or name Playwright/BrowserStack, none of which appear. This fits anchor 3 ('some relevant keywords but missing common variations or synonyms') better than 4, since several high-frequency trigger phrases are absent.

Distinctiveness Conflict Risk

The scope ("CI coverage, automated checks, or test strategy related to Test across all major browsers") carves a fairly distinct niche with a clear browser qualifier, matching 'mostly distinct; minor overlap risk'. It falls short of 5 because the generic terms 'CI coverage' and 'test strategy' could still pull in general CI-testing or lint-rule review skills before the browser qualifier applies.