Conciseness

The body is lean throughout: "Goal: record Time Profiler via xctrace, extract samples, symbolicate, and propose hotspots without opening Instruments", five numbered command blocks, and terse notes/gotchas — no explanation of concepts Claude already knows (what xctrace or ASLR tutorials, etc.). Every line earns its place, matching the 'Lean and efficient' anchor; there is no padding to justify a 4.

Actionability

Commands are fully executable and copy-paste ready with appropriate placeholders: "xcrun xctrace record --template 'Time Profiler' --time-limit 90s --output /tmp/App.trace --attach <pid>", "vmmap <pid> | rg -m1 \"__TEXT\" -n", and the two script invocations with real flags. The common cases (attach vs launch recording, empty stacks, ASLR load addresses) are each covered, matching the 'Fully executable' anchor.

Workflow Clarity

The five steps (record → extract → get load address → symbolicate/rank) are clearly numbered with rationale, and there are error-recovery hints ("If stacks are empty, capture longer or avoid idle sections", "Always confirm you're profiling the correct binary"). It falls short of the anchor-5 example's explicit validate-then-proceed checkpoints: there is no stated step to verify the trace contains samples or that the load address resolved before running symbolication, so it fits 'Clear sequence with most checkpoints present; minor validation gaps'.

Progressive Disclosure

The SKILL.md is a compact overview with well-organized sections (Quick start, Workflow notes, Included scripts, Gotchas), and the heavy logic is correctly pushed into bundle scripts — all three referenced paths (scripts/extract_time_samples.py, scripts/record_time_profiler.sh, scripts/top_hotspots.py) exist in the bundle. References are one level deep, clearly signaled in the 'Included scripts' section, and there is nothing that should have been split out further, matching the 'Clear overview with well-signaled one-level-deep references' anchor.

Specificity

The description "Native app performance: xctrace, Time Profiler, traces, hotspots." names the domain and tools but states no actions at all — it is a noun list, matching the anchor 'Names the domain but actions are minimal or generic'. It is not a 3 because that anchor requires 1-2 concrete actions (e.g., 'Records Time Profiler traces, symbolicates samples'), and none are stated.

Completeness

There is no 'when' clause at all ("Use when profiling a slow native app..." is absent), which caps completeness at 3 per the guidelines, and the 'what' is itself vague — no capability is stated, only topics/tools. This fits anchor 2 ('Has a vague what and no when') better than anchor 3, whose example lists explicit actions like 'Extract text and tables from PDF files'.

Trigger Term Quality

Terms like "Time Profiler", "xctrace", and "hotspots" are relevant and somewhat natural for this domain, but common variations a user would actually say are missing: "profile my app", "slow app", "CPU usage", "Instruments". This matches 'Some relevant keywords but missing common variations or synonyms' rather than a 4, which requires good coverage with only a few terms missing.

Distinctiveness Conflict Risk

"Native app performance" with xctrace/Time Profiler carves a fairly specific Apple-profiling niche that is unlikely to grab unrelated skills, though it could overlap with a generic performance-optimization skill and does not distinguish iOS vs macOS. This matches 'Mostly distinct; minor overlap risk' — not a 5, since the triggers are not distinctive enough to eliminate overlap with a broader performance skill.