arktype

Arktype: runtime validation, discriminated unions with .merge()/.or(), spread keys. Use when mentioning arktype, type(), union types, command/event schemas.

Quality

76%

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tessl review fix ./.agents/skills/arktype/SKILL.md

Quality

Content

75%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The body is highly actionable with copy-paste-ready arktype examples and good decision guidance for variant counts, but it is somewhat long for a single-file skill and re-explains library mechanics Claude largely already knows. Structure is solid though everything is inline with no separate reference files.

Suggestions

Trim the 'How it works' and 'Why this pattern'/'Why derive from constants' prose to the non-obvious points only, trusting Claude to infer standard union and merge mechanics.

Move the longer reference material (e.g. the full Merge Behavior and discriminant internals plus the inline source link) into a separate references file and link to it, keeping SKILL.md as a concise pattern overview.

Condense the repeated good/bad code pairs in Anti-Patterns to the single most illustrative contrast per pattern to reduce token cost.

Dimension	Reasoning	Score
Conciseness	Mostly efficient and dense with executable code, but several prose sections (the 'How it works', 'Why this pattern', 'Why derive from constants', and 'Merge Behavior' lists) re-explain mechanics Claude could largely infer, adding padding that could be trimmed.	3 / 5
Actionability	Fully executable, copy-paste-ready TypeScript across every pattern, with good/bad contrasts and constraint callouts covering the common composition cases.	5 / 5
Workflow Clarity	Patterns are clearly sequenced by use-case size (2-3 vs 4+ variants) with decision guidance and explicit constraints marking failure modes, though there are no formal validate/verify checkpoints because the skill is pattern-reference rather than a destructive multi-step operation.	4 / 5
Progressive Disclosure	Well-organized with clear section headers and a final References block, but all content lives inline in a single 380-line file with no bundle files to offload detail, so it stops short of the one-level-deep reference split a 5 assumes.	4 / 5
	Total	16 / 20 Passed

Description

78%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

The description is concise, specific, and clearly answers both what the skill does and when to use it, with strong distinctiveness tied to the named arktype library. It is held just below top marks only because the trigger and capability lists are compact rather than exhaustive.

Dimension	Reasoning	Score
Specificity	Lists several concrete actions — 'runtime validation', 'discriminated unions with .merge()/.or()', 'spread keys' — giving solid coverage of capabilities, but they are slightly abbreviated and lack the fuller action set a 5 would show.	4 / 5
Completeness	Answers both 'what' (validation, unions, merge/or, spread keys) and 'when' ('Use when mentioning arktype, type(), union types, command/event schemas'), but the 'when' clause is a single tight trigger list rather than the fuller explicit phrasing a 5 requires.	4 / 5
Trigger Term Quality	Good keyword coverage including 'arktype', 'type()', 'union types', 'command/event schemas' — natural terms a user would say — but misses some common variations or synonyms that would push it to 5.	4 / 5
Distinctiveness Conflict Risk	Clear niche tied to a named library with distinct triggers ('arktype', 'type()', 'command/event schemas'), making conflict with other skills minimal.	5 / 5
	Total	17 / 20 Passed

Validation

100%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository: EpicenterHQ/epicenter
Path: .agents/skills/arktype/SKILL.md
Commit: 825a995

Reviewed: 3 days ago

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