Conciseness

The body is dense and almost entirely novel API detail Claude cannot know (built-ins, TOML schemas, aggregation modes), with no filler explaining known concepts. It is not a 5 because a few passages could be trimmed or tightened — notably the shared-vs-separate environment paragraphs ("Put `[verifier].network_mode` only when verify() needs different network access... (a phase override, not a baseline)") and the single-paragraph wall of "Useful `[judge]` options" — but these are minor instances, matching the 4 anchor.

Actionability

Fully executable, copy-paste-ready guidance throughout: the exact `uvx --python '>=3.12,<3.14' --from 'harbor-rewardkit==0.2.*' rewardkit /tests` invocation, runnable Python and TOML snippets, directory layouts, and concrete output JSON. Specific examples cover the common cases (built-ins, custom criteria, LLM/agent/JEV judges, multi-reward aggregation). It is not a 4 because there are no gaps — even edge configuration (extras, env keys, CA certificates) is given concretely.

Workflow Clarity

Sections follow the natural authoring sequence — setup (test.sh, environments), then criteria types, then judges, then multi-reward/multi-step structure, then output files — with a "When to reach for what" decision guide. Validation feedback is partially present (reward-details.json exposes per-criterion results and errors), but there is no explicit "run the verifier locally and check reward-details.json before shipping" checkpoint loop, which keeps it below 5; the sequence and most checkpoints match the 4 anchor.

Progressive Disclosure

A single-file skill with no bundle, but well organized: clear hierarchical headers, an early worked example, a decision guide, and one clearly signaled external pointer ("See `examples/tasks/reward-kit-example/` in the Harbor repo"). It is not a 5 because at ~340 lines some reference-grade material (the full built-ins API list, the `[judge]` options catalog) is inlined in SKILL.md where a references/ file would keep the overview lean; it is not a 3 because structure and navigation are genuinely good, not merely present.

Specificity

The description lists multiple concrete actions — "creating or editing a task's tests/ directory", "adding grading criteria", "setting up LLM/agent judges", "designing verifiers that produce a reward score" — comprehensively covering the skill's main use cases. It is not a 4 because coverage of the distinct workflows (programmatic checks, judges, scoring) is complete for a description-length summary rather than having minor gaps.

Completeness

It explicitly answers both parts: what ("Write Harbor task verifiers using Reward Kit") and when ("Use when creating or editing a task's tests/ directory, adding grading criteria, setting up LLM/agent judges, or designing verifiers that produce a reward score") with concrete trigger phrases. This matches the anchor-5 example structure exactly; a 4 would require the 'when' clause to be less explicit or specific, which it is not.

Trigger Term Quality

Good natural keyword coverage: "task verifiers", "tests/ directory", "grading criteria", "LLM/agent judges", "reward score" — phrases a Harbor task author would plausibly say. It falls short of 5 because common synonyms and variations are missing (e.g., "scoring", "rubric", "evaluating", "test.sh"), whereas the 5 anchor expects comprehensive synonym/extension coverage.

Distinctiveness Conflict Risk

"Harbor task verifiers" and "Reward Kit" name a clear niche with distinct triggers (tests/ directory, grading criteria, judges) unlikely to fire for unrelated skills. It is not a 4 because the domain framing (Harbor/Reward Kit) leaves virtually no overlap risk with generic testing or document skills.