Conciseness

The ~50-line body is lean and assumes Claude's competence — e.g., "IAM 集成和本地 RBAC 数据是一条完整权限链，不应分开孤立看" adds non-obvious guidance without padding. The one trimmable redundancy is that the three reference paths are listed verbatim twice ("快速指导" item 3 and again in "延伸阅读"), matching anchor 4 ('efficient; minor instances that could be trimmed') rather than the every-token-earns-its-place anchor 5.

Actionability

The problem-type-to-document routing map ("模块结构与核心对象：`reference/1-auth-foundation.md`" etc.) is concrete, but the key diagnostic instruction "先判断是 Auth 平台问题还是业务侧传参问题" gives no criteria for making that judgment, and the routing targets (`reference/*.md`) do not exist in the provided bundle — no `reference/` or `references/` directory is present — so the primary action cannot actually be executed here. This matches anchor 3 ('some concrete guidance but incomplete; missing key details') rather than anchor 4.

Workflow Clarity

"快速指导" lays out a clear numbered decision sequence — classify the problem type, route to the matching reference, switch to `permission-model-change-guide` when designing new resource types, then classify platform-vs-caller failures — which is coherent for a routing skill with no destructive operations. It stops short of anchor 5 because the classification steps lack explicit checkpoints/criteria (e.g., how to tell an Auth platform issue from a business-side parameter issue).

Progressive Disclosure

The written structure is good — a concise overview with clearly labeled, one-level-deep references ("RBAC、用户组与授权链路：`reference/2-rbac-group-authorization.md`") — but those referenced files are not present in the bundle being evaluated (no `reference/`, `references/`, `scripts/`, or `assets/` directories exist), so the navigation the skill depends on cannot be verified to resolve. Per the guideline to score against the actual bundle structure, this drops it to anchor 3; with the referenced files present it would merit 5.

Specificity

The description enumerates five concrete capability areas — "RBAC 权限校验、用户组与资源管理、IAM 集成、授权迁移和 OAuth2 认证" — under the umbrella verb "处理" (handle), which is specific but more a list of domains than distinct executable actions, matching anchor 4 ('lists several specific actions; minor gaps') rather than the fully action-verb-driven anchor 5.

Completeness

It explicitly answers both questions: what it covers ("RBAC 权限校验、用户组与资源管理、IAM 集成、授权迁移和 OAuth2 认证") and when to use it ("处理 BK-CI Auth 模块时使用" plus "当用户要改权限平台实现而不是单次权限模型变更时优先使用" — a concrete, discriminating trigger phrase), matching anchor 5. It is not anchor 4 because the 'when' is not merely present but explicitly disambiguated against a sibling skill.

Trigger Term Quality

Strong natural keywords a BK-CI contributor would actually say — "RBAC 权限校验", "用户组", "IAM 集成", "OAuth2", "授权迁移", "权限平台" — giving good coverage; a few common variations (e.g., 权限排查/debugging phrases, login/authentication wording, English equivalents) are missing, so it fits anchor 4 rather than the comprehensive synonym coverage of anchor 5.

Distinctiveness Conflict Risk

It is tightly scoped to the "BK-CI Auth 模块" niche and actively reduces conflict risk by stating "当用户要改权限平台实现而不是单次权限模型变更时优先使用" — explicitly separating itself from a single permission-model change — matching anchor 5 (clear niche with distinct triggers, minimal conflict risk).