Conciseness

The body is lean and command-driven with no concept explanations Claude already knows — every section is a code block or table. Minor duplication keeps it off score 5: the Providers table repeats the four `cua do switch` variants already shown in Setup, and the Quick Reference table overlaps the separate command-reference.md. Not score 3: there is no unnecessary explanation or padding, only redundant structure.

Actionability

Every example is a copy-paste-ready shell command with concrete coordinates ("cua do click 450 280", "cua do type 'Jane Doe'") covering the common cases: clicking, form filling, file-upload dialogs, zoom for precision, drag-and-drop, and fuzzing. This matches the score-5 anchor (fully executable, covers common cases); not score 4: there are no gaps in executable detail.

Workflow Clarity

The core loop is explicit — "Look → Act → Verify: repeat until done" — with built-in validation (screenshot after every action) and error-recovery feedback: "Re-screenshot after every UI change: coordinates go stale when the screen changes" and "Use `zoom` any time click accuracy is uncertain". This matches the score-5 anchor (clear sequence, explicit validation, feedback loops); not score 4: checkpoints are explicit throughout, not merely implied.

Progressive Disclosure

Good structure: workflow and common scenarios live in SKILL.md while full argument syntax is correctly split into the real, one-level-deep references/command-reference.md, signaled via a clear link. Minor gaps keep it at 4: the link to the reference file appears only at the very bottom (buried after two tables), and the 20-row Quick Reference table partially duplicates the reference file's content — the anchor-4 pattern of "most content appropriately placed; minor organization gaps". Not score 3: the split is appropriate and the reference is clearly signaled, not buried or multi-level.

Specificity

The description lists multiple concrete actions — "test buttons, fill forms, verify visual layouts, fuzz web pages, automate user flows, take screenshots, or perform end-to-end QA" — which matches the comprehensive score-5 anchor, but it is written in second person ("Use when you need to visually interact with a GUI"), which the rubric penalizes by 1 point on specificity. Not score 3: far more than 1-2 concrete actions are named; not score 5: the second-person voice penalty applies.

Completeness

Explicitly answers both questions: "what" via the concrete action list (test buttons, fill forms, fuzz, screenshots, e2e QA) and "when" via the explicit trigger clause "Use when you need to visually interact with a GUI", plus environment scope ("cloud VMs, Docker containers, local machines, and sandboxes") and the dependency ("Needs the `cua` CLI"). This matches the score-5 anchor's what+when with concrete trigger phrases; not score 4: the "when" is explicit and leading, not merely appended.

Trigger Term Quality

Strong natural phrases users would actually say: "test buttons", "fill forms", "take screenshots", "automate user flows", "end-to-end QA", "fuzz web pages" — good coverage with synonymous phrasings. Not score 5: a few common natural terms are missing, e.g. "click", "scroll", "UI testing", "browser automation"; not score 3: coverage goes well beyond bare domain keywords with multiple synonyms for the core need.

Distinctiveness Conflict Risk

The niche — visual GUI interaction via a specific `cua` CLI on cloud VMs/sandboxes/containers — is mostly distinct with a clear tool identifier. Not score 5: phrases like "take screenshots" and "end-to-end QA" on "any application" carry minor overlap risk with browser-automation or screenshot-oriented skills; not score 3: the coordinate-clicking/screen-automation framing tied to `cua` is far more specific than generic document/file skills.