Lists multiple specific concrete actions: 'investigate history, usage, and liveness of code', 'search and git blame/log', 'determining if code is dead', 'finding all callers before refactoring', 'deciding whether something is safe to remove'. These are concrete, actionable capabilities.

Clearly answers both what ('Investigate the history, usage, and liveness of code using search and git blame/log') and when ('Use when determining if code is dead, understanding why something exists, finding all callers before refactoring, or deciding whether something is safe to remove'). Has an explicit 'Use when' clause with multiple trigger scenarios.

Excellent coverage of natural terms users would say: 'dead code', 'git blame', 'git log', 'refactoring', 'callers', 'who added this and why', 'is anything still using this', 'safe to remove'. These closely match how developers naturally phrase these questions.

Occupies a clear niche around code archaeology and liveness analysis using git history tools. The specific focus on dead code detection, blame investigation, and pre-refactoring caller analysis distinguishes it well from general code search or refactoring skills.

Every section earns its place. No explanation of what git blame is or how grep works — it jumps straight to the specific patterns Claude needs. The decision framework table is dense and useful. No filler.

Provides fully executable git and grep commands with concrete flags and patterns. The git commands reference section is copy-paste ready, and the techniques section shows exactly how to interpret results (e.g., 'classify hits as definition, test, re-export, or real caller').

The skill explicitly says 'pick whichever techniques are useful' rather than forcing a rigid sequence, which is appropriate for an investigative task. The decision framework table provides clear validation checkpoints (what evidence leads to what verdict), and the output format gives a structured 5-step reporting sequence. The workflow naturally includes verification (checking transitive usage, checking re-exports).

For a standalone skill under 50 lines with no need for external references, the content is well-organized into logical sections: techniques, decision framework, output format, and command reference. The structure supports quick scanning and progressive depth.