Conciseness

The body is dense, imperative, and free of concepts Claude already knows — every line carries a rule, caveat, or concrete parameter (e.g., "Pass `window_id` whenever one is known so unrelated applications cannot consume the node budget"). It sits at 4 rather than 5 because the screenshot-as-proof rule is restated several times ("Use screenshots for proof after every state-changing action", "Treat every shortcut as an attempt. Inspect the fresh screenshot before saying it worked", "an accepted AT-SPI call without active/focused state is not activation proof") and could be consolidated.

Actionability

Two complete, copy-paste-ready `computer_use_remote` JSON tool calls (`ax_snapshot`, `ax_action`) with concrete parameters, an enumerated operation list (`press`/`focus`/`set_value`), concrete error codes (`COMPUTER_USE_WINDOW_REQUIRED`, `COMPUTER_USE_TARGET_NOT_FOCUSED`, `COMPUTER_USE_AX_UNAVAILABLE`), specific shortcuts, and an ordered fallback chain. This covers the common cases fully, matching the top anchor; score 4 would require missing key details, and there are none of consequence.

Workflow Clarity

There is an explicit conditional flow ("prefer the generic background loop from `host-computer-use`: `list_windows` -> `get_window_state` -> `element_action`. If those features are absent, use the AT-SPI snapshot/action flow below") plus snapshot-choose-act-verify feedback loops ("If an action reports ambiguity, take a fresh snapshot and narrow the target") and validation checkpoints ("Continue only when the result says `focus_verified=true`"). It stays at 4 rather than 5 because the end-to-end sequence is distributed across sections rather than presented as one ordered checklist, so a reader must assemble the order themselves.

Progressive Disclosure

No references/, scripts/, or assets/ directories exist, and the single ~95-line body is well-sectioned (AT-SPI Targeting, Wayland Notes, Permissions) with no nested or buried references, so there is no navigation failure. It is a 4 rather than 5 because the GNOME shortcut list and the permission/error-code catalogs are inline reference material that could live in a one-level-deep reference file, and the skill exceeds the under-50-lines simple-skill case.

Specificity

"Covers AT-SPI structural targeting, Wayland portal caveats, and screenshot verification" lists several concrete capability areas for "Backend-specific Linux guidance for `computer_use_remote`", matching the 'several specific actions; minor gaps' anchor. It falls short of 5 because items like window-list integration, text injection, and permission handling are not mentioned, and 'caveats' is a topic rather than an action.

Completeness

Both halves are explicit: the what ("Backend-specific Linux guidance for `computer_use_remote`... Covers AT-SPI structural targeting, Wayland portal caveats, and screenshot verification") and the when ("Load after `status` or `start_session` reports backend_family `linux`, backend_id `wayland`, or AT-SPI features") with concrete trigger conditions. This matches the top anchor exactly; a 4 would require the when to be less explicit than this.

Trigger Term Quality

Strong, relevant keywords: "backend_family `linux`", "backend_id `wayland`", "AT-SPI features", "structural targeting", "screenshot verification" — good coverage with only a few natural terms missing. Not 5 because common variations a user might say ("Linux desktop", "GNOME", "accessibility tree") are absent.

Distinctiveness Conflict Risk

"Backend-specific Linux guidance" scoped to `computer_use_remote` with load conditions keyed on Linux/Wayland/AT-SPI backend reports carves a clear niche with distinct triggers and minimal conflict risk. Neighboring anchor 4 ('minor overlap risk') does not fit because the description explicitly names its parent skill, load timing, and backend family, leaving almost no ambiguity with generic computer-use skills.