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core

Core package for defining schemas, catalogs, and AI prompt generation for json-render. Use when working with @json-render/core, defining schemas, creating catalogs, or building JSON specs for UI/video generation.

Quality

82%

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SKILL.md
Quality
Evals
Security

Quality

Content

71%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.

A dense, largely executable API reference with strong code examples and useful feedback-loop guidance, held back by its monolithic single-file structure. The experimental composition section and the exports table should live in reference files with SKILL.md as a lean overview.

Suggestions

Split the skill into a lean SKILL.md overview plus references/ files (e.g., references/exports.md for the Key Exports table, references/composition.md for the experimental decision-model section) and link to them with clear 'See X for Y' signals.

Tighten the 'Experimental Decision-Model Composition' section: convert its multi-clause paragraphs into scannable bullets or tables and remove the duplicated $bindState guidance (it appears both in the bullet list and again under 'Components do not use a statePath prop').

Replace or back the pointers to 'packages/core/README.md' and '/docs/jev' with actual files in the skill's references/ directory so navigation stays one level deep inside the bundle.

DimensionReasoningScore

Conciseness

The body is dense and information-bearing with almost no explanation of concepts Claude already knows (e.g., the expression reference and exports table are pure API facts). Not 5 because the 'Experimental Decision-Model Composition' section is a wall of multi-clause paragraphs that could be tightened, and the $bindState guidance is stated twice (bullet list and again in 'Components do not use a statePath prop...'); not 3 because padding is minor, not 'several unnecessary explanations'.

4 / 5

Actionability

Mostly executable copy-paste TypeScript/JSON: 'defineSchema', 'defineCatalog', 'createSpecStreamCompiler', 'visibility.when("/path")', and the StateStore usage all show runnable code. Not 5 because the schema example contains placeholder pseudocode ('// Define spec structure' inside s.object) and some snippets (e.g., check helpers) lack a usage context; not 3 because the gaps are small relative to the volume of executable guidance.

4 / 5

Workflow Clarity

As a reference-style skill it needs no multi-step sequence, and where sequencing matters it is explicit: the repair-loop guidance ('In a repair loop, withhold lossy fixes until retries are exhausted: autoFixSpec(spec, { lossy: retriesExhausted })') is a concrete validate/fix/retry feedback loop. Not 5 because there is no guided order for consuming the sections and some multi-part flows (schema -> catalog -> prompt) are only implied by section order; not 3 because the per-task sections are unambiguous.

4 / 5

Progressive Disclosure

No bundle files exist (references/, scripts/, assets/ are absent), so ~296 lines of full API reference — including the 25-row Key Exports table and the experimental composition deep-dive — are inlined in SKILL.md, matching the anchor '[200 lines of API reference that could be in a separate file]'. The only pointers ('See packages/core/README.md and /docs/jev') target repo paths, not skill bundle files, so they are not well-signaled one-level-deep references. Not 4 because content that clearly belongs in separate reference files is inline; not 2 because section headers do provide navigable structure.

3 / 5

Total

15

/

20

Passed

Description

83%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.

A strong description with a clear what-and-when structure, third-person voice, and concrete package-scoped triggers. Its only weaknesses are coverage gaps (unmentioned capabilities like spec streaming and validation) and the slightly generic 'defining schemas' trigger that invites overlap with unrelated schema skills.

DimensionReasoningScore

Specificity

"defining schemas, catalogs, and AI prompt generation" names several concrete actions in the json-render domain, matching the 'lists several specific actions; minor gaps' anchor. Not 5 because the body exposes many more capabilities (spec streaming, validation, state stores, prop expression resolution) that the description omits; not 3 because it goes beyond 1-2 actions.

4 / 5

Completeness

It answers 'what' explicitly ("Core package for defining schemas, catalogs, and AI prompt generation for json-render") and 'when' explicitly with concrete trigger phrases ("Use when working with @json-render/core, defining schemas, creating catalogs, or building JSON specs for UI/video generation"), matching the top anchor exactly.

5 / 5

Trigger Term Quality

Triggers like "@json-render/core", "defining schemas", "creating catalogs", and "building JSON specs for UI/video generation" give good natural keyword coverage a user would plausibly say. Not 5 because common synonyms such as spec streaming, validation, or state/state-store work are missing; not 3 because coverage is clearly better than 'some relevant keywords'.

4 / 5

Distinctiveness Conflict Risk

"@json-render/core" and "JSON specs for UI/video generation" carve out a distinct niche, but the trigger "defining schemas" is broad and could overlap with generic schema-tooling skills. Not 5 due to that overlap risk; not 3 because the package-scoped triggers are far more specific than 'somewhat specific'.

4 / 5

Total

17

/

20

Passed

Validation

100%

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

vercel-labs/json-render

Path

skills/core/SKILL.md

Reviewed

Table of Contents

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