Conciseness

The body is lean and assumes BGP competence: every section is commands, a state-interpretation table, or a non-obvious operational caveat (e.g., the `_65001_` token-boundary regex warning and the received-routes configuration trap). No tokens are spent explaining concepts Claude already knows, matching anchor 5; it is not a 4 because there is no over-explanation to trim.

Actionability

Copy-paste-ready command blocks for every phase (triage, transport, policy, AS path), a complete executable Python parser with a compiled regex, and specific conditional guidance for VRF/IPv6/EVPN. This fully matches anchor 5 ("copy-paste ready code or commands; specific examples cover the common cases").

Workflow Clarity

The five-step Read-Only Triage Flow is clearly sequenced with meaningful checkpoints ("Check route policy references before assuming transport failure", "Prove reachability to the peer source address"), and the state table gives per-state next actions. It falls just short of anchor 5's explicit validation/checklist formality — there is no explicit verify-before-concluding or escalation step closing the loop — and comfortably above anchor 3 since checkpoints are explicit, not implicit.

Progressive Disclosure

Sections are well-organized and appropriately sized for a single file with no bundle structure present, fitting anchor 4 ("good structure; most content appropriately placed; minor organization gaps"). It is not a 5 because the ~40-line parser example is inlined where a scripts/ file would fit, and platform-specific variants (VRF/IPv6/EVPN command syntax) are deferred with no reference file to carry them.

Specificity

The description enumerates five concrete capability areas ("neighbor state, route exchange, prefix policy, AS path inspection, and safe evidence collection") with minor gaps — it names inspection domains rather than discrete actions such as parsing BGP summary output. It sits between anchor 3 (1-2 actions) and anchor 5 (fully comprehensive action list), fitting anchor 4 best.

Completeness

It explicitly answers both what ("Diagnostics-only BGP troubleshooting patterns for neighbor state, route exchange...") and when ("Use when a BGP neighbor is down, routes are missing, or prefix policy and AS path need inspection") with concrete trigger phrases, matching the anchor 5 example pattern. It is not a 4 because the when-clause is explicit and specific rather than merely present.

Trigger Term Quality

"BGP neighbor is down", "routes are missing", and "prefix policy and AS path" are phrases users would naturally say, giving good keyword coverage. Common synonyms like "BGP flapping", "peering", or "session down" are missing, so it fits anchor 4 rather than the comprehensive synonym coverage of anchor 5.

Distinctiveness Conflict Risk

"Diagnostics-only" combined with BGP-specific triggers carves a clear niche distinct from general network config or interface-health skills, with minimal conflict risk. The body's See Also references to sibling skills confirm the boundary is deliberate.