Conciseness

The body is mostly efficient domain-specific guidance, but the re-run-mode rules for existing App-Brief.md files are repeated nearly verbatim in three places (Operating rules bullet, Step 0 rule 4, and the 'Re-run mode for support fields' section), and 'never invent' is stated three times — clear cases where it could be tightened. It is above 2 because there is no explanation of concepts Claude already knows; the length comes from real domain content plus duplication.

Actionability

Fully executable instruction-only guidance: verbatim challenge prompts per coached field, exact commands ("npx @cognite/cli@latest apps skills pull"), a sentinel glob pattern, fixed four-option supportPath choices, and a copy-paste-ready App-Brief.md template with exact YAML frontmatter. Specific examples (the shift-supervisor persona, the handover problem) cover the common cases.

Workflow Clarity

The Preflight through Step 6 sequence is explicit, with validation checkpoints and feedback loops: the skills-pull sentinel check offers Retry/Skip/Stop, and Step 5 refuses to write the file and returns to coaching while any required field is empty. It also handles the re-run and edge cases (single maintainer warning, string-vs-list maintainer). Not a destructive or batch operation, so no cap applies.

Progressive Disclosure

A single-file skill with no bundle directories, well-organized under numbered step headers and tables, and one clearly signaled one-level-deep reference ([start-flows-app](../start-flows-app/SKILL.md)). It is not a 5 because the ~65-line output template in Step 5 is content that could be split into a reference/asset file, keeping SKILL.md as a leaner overview.

Specificity

The description lists several concrete actions — "Captures the app name, value case, persona, problem, and design intent", "writes App-Brief.md at the repo root", "follow start-flows-app" — placing it at the 'several specific actions; minor gaps' anchor. It falls short of 5 because procedural asides ("do not dump an empty template as the opening move", "so https://localhost is up first") pad the capability list rather than broaden coverage.

Completeness

It explicitly answers both what ("Captures the app name, value case, persona, problem, and design intent... and writes App-Brief.md") and when ("Use when the user asks to start an app brief, run the certification coach, fill out the app brief, or run flows-app-brief") with concrete trigger phrases, matching the top anchor. A 4 would require the 'when' clause to be less explicit, which is not the case here.

Trigger Term Quality

"Use when the user asks to start an app brief, run the certification coach, fill out the app brief, or run flows-app-brief" gives good keyword coverage of natural phrasings. It is not a 5 because common variations such as "create an app brief" or "app briefing" are missing.

Distinctiveness Conflict Risk

"Certification coach for Flows apps" carves a clear niche with flow-specific triggers ("flows-app-brief", "certification coach"), but it sits in a five-skill certification pipeline where sibling skills (build, code-review, design-review) could plausibly fire on adjacent phrasings — minor overlap risk with closely related skills. Not a 5 because the niche is distinct but the pipeline context creates some adjacency.