Lists multiple specific concrete actions and domains: injection types (SQL, command, XSS), cryptography, filesystem safety, network security, cookies, secrets management, memory safety, logging, and security tools configuration.

Clearly answers both 'what' (security best practices covering injection, crypto, filesystem, network, cookies, secrets, memory, logging) and 'when' ('Apply when writing, reviewing, or auditing Go code for security, or when working on any risky code involving crypto, I/O, secrets management, user input handling, or authentication').

Includes strong natural keywords users would say: 'SQL', 'XSS', 'command injection', 'crypto', 'secrets management', 'user input handling', 'authentication', 'Go code', 'security', 'auditing'. Good coverage of terms a developer would use when seeking security guidance for Go.

Clearly scoped to Golang security specifically, with distinct triggers around Go code security auditing, vulnerability prevention, and specific security domains. Unlikely to conflict with general Go coding skills or security skills for other languages.

The skill is reasonably efficient but includes some unnecessary framing (e.g., the 'Security Thinking Model' section explains concepts Claude already knows about threat modeling). The tables and quick reference are dense and useful, but the anti-patterns and common mistakes tables have some redundancy with each other and with the referenced files. The persona/modes preamble adds value but is slightly verbose.

The skill provides concrete tool commands (gosec, govulncheck, go test -race) and a useful quick-reference table mapping vulnerabilities to standard library solutions. However, it lacks executable code examples for the most critical patterns (e.g., no parameterized SQL example, no exec.Command safe usage example) — those are deferred to reference files. The tables describe fixes in prose rather than showing them.

The three modes (Review, Audit, Coding) are clearly defined with distinct workflows. The audit mode specifies parallel sub-agents with explicit domains. The 'Research Before Reporting' section provides a clear 4-step validation workflow with severity adjustment guidance and documentation requirements. The review mode includes tracing data flows beyond the diff, which is a validation checkpoint.

Excellent progressive disclosure structure: the main file serves as a clear overview with a quick-reference table, then points to 12 well-organized reference files covering specific domains (cryptography, injection, filesystem, etc.). References are one level deep, clearly signaled with descriptive labels, and organized logically. Cross-references to other skills are also included.