Conciseness

The body is ~20 lines with zero concept explanations or padding, and the redirect ("Use `testing-best-practices` for all test design, test case generation, and test strategy work") earns its tokens. The 7-bullet "What changed" migration history is context Claude does not need once redirected, so it could be trimmed — anchor 4 rather than 5.

Actionability

The core instruction is concrete, unambiguous, and scope-explicit: "Use `testing-best-practices` for all test design, test case generation, and test strategy work." Minor gap: the pointer relies on the bare skill name with no path or link to the replacement, keeping it just under the fully copy-paste-ready anchor 5.

Workflow Clarity

This is a single-action skill (redirect to the replacement) and that action is unambiguous, stated twice, and scoped to the full former domain. Per the simple-skill rule, a single unambiguous action warrants 5; no validation checkpoints are needed since nothing destructive is performed.

Progressive Disclosure

At ~20 lines with no bundle files (no references/, scripts/, or assets/ exist) and no need for external detail, the content is appropriately self-contained in one well-organized file with clear sections ("## Deprecated", "### What changed"). Per the short-skill rule this warrants 5.

Specificity

The description contains one concrete directive ("Use testing-best-practices instead") plus the status statement "This skill has been retired", but names no domain and describes no capabilities. It sits between the entirely-vague anchor 1 and the minimal-actions anchor 2 — the redirect is concrete, but nothing else is.

Completeness

Neither a capability "what" nor a "when" trigger clause is present; the only explicit content is deprecation status and a redirect. Score 2 rather than 1 because the redirect statement is clear and actionable rather than vague; score 3 is ruled out because the "clear what" anchor presumes described capabilities, which are entirely absent.

Trigger Term Quality

There are no natural keywords users would say when needing this skill's domain — "testing-best-practices" is a skill name, not a user phrase, and "skill has been retired" is generic meta-language. This matches anchor 1 (no natural keywords, only technical jargon or generic language).

Distinctiveness Conflict Risk

The description claims no distinct niche — it overlaps entirely with the testing-best-practices territory — but the explicit "Use testing-best-practices instead" deferral makes any triggering conflict benign, since it would route users to the correct skill. Anchored at 3 (somewhat specific but overlapping); not 4 because it establishes no distinctive triggers of its own.