Conciseness

At roughly 58 lines, every section (Quick start, Why, Workflow, Anti-patterns, Checklist, See also) earns its place: it explains only tool-specific behavior ('When the lookup gives commit: null, the commit predates session linking') and nothing Claude already knows. It matches anchor 5 — lean, assumes competence, no trimmable padding.

Actionability

The Quick start gives a fully worked, copy-paste-ready example with expected output, and the Workflow supplies exact command templates per input type ('git blame -L <start>,<end> <file>', 'git log -L :<function>:<file>', 'memory_commit_lookup { "sha": "<full-sha>" }'). The only gap is that the optional memory_recall invocation syntax is not shown, which does not undermine the common path — matching anchor 5's 'copy-paste ready commands covering common cases'.

Workflow Clarity

A clear 3-step sequence with per-input-type variants, an explicit Checklist serving as validation ('SHA came from git blame/log, not a guess'), and a WRONG/RIGHT anti-pattern pair giving an error-recovery path for the commit: null case. This read-only skill has no destructive/batch operations, so the validation cap does not apply; the checklist plus null-handling loop matches anchor 5.

Progressive Disclosure

The single-file body is well organized into clearly signaled sections, and the one external reference ('See [TROUBLESHOOTING.md](TROUBLESHOOTING.md)') is one level deep and clearly motivated. However, TROUBLESHOOTING.md does not exist in the bundle (no references/ or other files are present), so the link is dangling — a minor organization gap that fits anchor 4 ('references mostly clear; minor organization gaps') rather than anchor 5's 'easy navigation'.

Specificity

The description states a precisely defined concrete action — 'Trace a file, function, or line back to the agent session that produced its current commit' — covering three input types with an exact domain (git commits, agent sessions). It sits between anchor 3 (1-2 concrete actions, not comprehensive) and anchor 4 (several specific actions): the single action is more exact and input-enumerated than anchor 3, but it is one action rather than a list of several, so it does not fully reach anchor 4's coverage.

Completeness

Sentence one explicitly answers 'what' ('Trace a file, function, or line back to the agent session that produced its current commit') and sentence two explicitly answers 'when' with concrete quoted trigger phrases, matching the anchor 5 example structure exactly. It uses third-person/declarative voice with no first- or second-person phrasing.

Trigger Term Quality

The quoted phrases 'why is this code here', 'what was the agent doing when this changed', 'who wrote this', and 'wants context on a specific location' are literal natural user utterances — exactly what triggers should be. It falls short of anchor 5 because common synonyms are missing (e.g., 'who changed this', 'when was this added', 'blame').

Distinctiveness Conflict Risk

The agent-session-tracing niche is distinct with dedicated triggers like 'what was the agent doing when this changed'. Minor overlap risk remains: 'who wrote this' could plausibly trigger a plain git-blame or git-history skill, and the body itself references sibling skills ('commit-history', 'recall') in the same domain, so it is mostly distinct rather than having minimal conflict risk.