Lists multiple specific concrete actions: creating, updating, and deprecating hybrid cloud RPC services, plus details like service scaffolding, method signatures, RPC models, cell resolvers, testing, and safe deprecation workflows.

Clearly answers both 'what' (creating, updating, deprecating hybrid cloud RPC services, covering scaffolding, method signatures, models, resolvers, testing, deprecation workflows) and 'when' (explicit 'Use when asked to...' clause with nine specific trigger phrases).

Excellent coverage of natural trigger terms users would say: 'add RPC method', 'create RPC service', 'hybrid cloud service', 'new RPC model', 'deprecate RPC method', 'remove RPC endpoint', 'cross-silo service', 'cell RPC', 'control silo service'. These are domain-specific but exactly what a developer in this context would naturally type.

Highly distinctive with a clear niche: Sentry hybrid cloud RPC services. The combination of domain (Sentry), technology (RPC/hybrid cloud), and specific terminology (cell resolvers, cross-silo, control silo) makes it very unlikely to conflict with other skills.

The skill is mostly efficient and domain-specific, but the testing section (Step 7) is quite extensive with many code examples that could be split into a reference file. Some patterns like error propagation examples add bulk. However, most content is genuinely novel project-specific knowledge Claude wouldn't have.

Excellent actionability throughout — concrete directory structures, executable code examples with correct syntax, specific decorator ordering rules, exact grep commands for checking uniqueness, and copy-paste-ready test patterns. Every step provides specific, implementable guidance.

The workflow is clearly sequenced with a decision table in Step 1, explicit ordering through Steps 2-8, a comprehensive pre-flight checklist in Step 8, and validation checkpoints throughout (e.g., decorator ordering, backwards compatibility rules, two-phase breaking change approach). The safe vs. breaking changes distinction in Step 5 is a good validation checkpoint.

The skill references external files well (references/resolvers.md, references/service-template.md, references/rpc-models.md, references/deprecation.md) with clear signaling. However, the testing section (Step 7) is very long and inline — it could benefit from being split into a separate reference file. The main body is ~300+ lines which is heavy for a SKILL.md overview. No bundle files were provided to verify the referenced paths exist.