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 generally well-organized but includes some unnecessary explanatory content that Claude already knows (e.g., explaining what STRIDE stands for, explaining why MD5 is bad, explaining what defense in depth means). The 'Security Thinking Model' and 'Research Before Reporting' sections add value but could be tighter. The tables are efficient, but the overall document is on the verbose side for a skill that delegates most detail to reference files.

The skill provides concrete tool commands (gosec, govulncheck, go test -race) and a useful quick reference table, but most actionable content is deferred to reference files. The main skill body contains no executable Go code examples for the vulnerabilities it lists — the 'Common Mistakes' table says what to do but doesn't show how. The audit/review mode descriptions are procedural but lack concrete step-by-step commands.

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 investigation workflow with severity adjustment guidance and documentation requirements. The review mode includes tracing data flows beyond the diff. Validation is addressed through tooling (gosec, race detector, govulncheck).

Excellent progressive disclosure — the main skill provides a concise overview with quick reference tables, then clearly signals 11 one-level-deep reference files covering specific domains. Each reference link includes a brief description of what it covers. The checklist, threat modeling guide, and architecture references are all clearly signaled and appropriately separated.