The body is mostly lean and table-driven (SAQ table, PAN-storage rules, anti-patterns table), but the "distinct from a scope checker" distinction is restated redundantly — once in the opening ("This skill is distinct from a scope checker… This skill explains what the boundary IS") and again at the close ("A `pci-dss-control-test-author` runs these adversarially. This skill provides the catalog.") — despite already appearing in the description. That places it at the score-2 'mostly efficient but could be tightened' level rather than the 'every token earns its place' score-3 level.

Provides concrete, executable material: a PostgreSQL regex SQL block for detecting PAN, an HTML example for the Stripe Element, and specific gateway API names (Stripe `setupIntent`, Adyen `paymentMethods.storeDetails`, PayPal Vault). This is 'specific examples; copy-paste ready' guidance rather than the pseudocode/vague level of score 2.

The 'How to use this catalog' section gives a clear 3-step sequence (identify pattern → determine SAQ level → verify testable behaviours) with a verification checkpoint in step 3 ("Cross-reference the Testable behaviours table and anti-patterns to confirm the scope boundary is preserved"). This is a reference catalog with no destructive/batch operations, so the missing-feedback-loop cap does not apply, and the explicit verify step clears score 3.

No bundle files are present (references/, scripts/, assets/ absent), so scoring is against the body organization: it is a compact (~157 line) single-file catalog with clearly headed sections (SAQ levels, PAN storage, Scope-reduction patterns, Testable behaviours, Anti-patterns, Limitations, References) and one-level-deep external links clearly signaled in a References section. Easy navigation and no nested references fit score 3; it is not the monolithic/nested wall of text that defines score 1.

Lists multiple specific concrete capabilities: "SAQ levels (A through D)", "PAN-storage prohibitions (only first-6 + last-4 retained; nothing else cleartext)", "tokenization + hosted-fields scope-reduction patterns (Stripe Elements / Adyen Drop-in / Braintree Hosted Fields)" and "Network-Segmentation as PCI scope-reduction" — matching the score-3 anchor of multiple specific actions, not the vaguer score-2 level.

Explicitly answers both what ("Pure-reference catalog of PCI DSS v4.0 scope reduction techniques + the testable scope boundaries") and when ("Use when designing or auditing the PCI scope of a payment integration"), with a present 'Use when' clause — so it clears the cap that a missing trigger would impose at 2.

Covers natural terms a PCI-compliance user would say — "PCI DSS", "PCI scope", "scope reduction", "payment integration" — anchored by the explicit trigger "Use when designing or auditing the PCI scope of a payment integration". It is not merely jargon (score 1) nor missing common variations (score 2); the trigger clause itself reads naturally.

Occupies a clear niche (PCI scope reference catalog) and explicitly disambiguates from the adjacent skill: "not a checker that verifies a given integration against the standard". This distinct trigger boundary makes wrong-skill conflicts unlikely, fitting the score-3 anchor rather than the overlapping score-2 level.