yjs

Yjs CRDT patterns, shared types (Y.Map, Y.Array, Y.Text), transactions, y-protocols sync and awareness, y-indexeddb persistence, conflict resolution, and document storage. Use when mentioning Yjs, Y.Doc, CRDTs, collaborative editing, real-time sync, awareness, IndexeddbPersistence, or Yjs providers.

Quality

82%

Does it follow best practices?

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Securityby

Passed

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Quality

Content

65%

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

A knowledgeable, code-rich Yjs reference with excellent actionability, but it is long and mixes a basic primer plus an oversized inline abstraction-leaks tutorial with the core patterns, and its destructive-storage operations lack explicit validation loops.

Suggestions

Move the full abstraction-leaks tutorial (the 'Boundary Rule' diagram and 'How to Spot Abstraction Leaks' list) into the referenced docs/articles/yjs-abstraction-leaks-cost-more-than-the-abstraction.md file and keep only a brief pointer in SKILL.md, since that file does not currently exist.

Tighten the 'Shared Types' primer — drop the 'like JavaScript Map/Array' glosses Claude already knows and keep only the Yjs-specific notes (e.g. the six-type inventory and editor-integration caveat).

Add an explicit validate→fix→retry checkpoint around the clearData reset and epoch-compaction flows (e.g. 'verify no active writers, then clearData, then re-hydrate and confirm state') to satisfy the destructive/batch-operation feedback-loop requirement.

Dimension	Reasoning	Score
Conciseness	Dense expert material with little concept padding, but the ~360-line body includes a basic shared-types primer ('Y.Map - Key-value pairs (like JavaScript Map)') and a lengthy inline abstraction-leaks tutorial with an ASCII diagram that could be tightened or moved out.	2 / 3
Actionability	Multiple complete, executable TypeScript snippets (single-writer counters, fractional indexing, nested maps, epoch compaction, debugging) plus specific API calls, all copy-paste oriented.	3 / 3
Workflow Clarity	The 'Upstream Grounding' procedure is a clear verify-before-changing loop, but destructive operations like the clearData reset and compaction lack explicit validate→fix→retry checkpoints, capping workflow clarity per the destructive-ops feedback-loop guideline.	2 / 3
Progressive Disclosure	Well-headed sections and one-level-deep references, but no bundle files exist so the referenced local article path (docs/articles/...) is dangling, and the large inline abstraction-leaks tutorial is content that arguably should live in the referenced file rather than inline.	2 / 3
	Total	9 / 12 Passed

Description

100%

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: specific capabilities, broad natural trigger terms, explicit when-to-use guidance, and a clearly distinct Yjs niche. No notable weaknesses to address.

Dimension	Reasoning	Score
Specificity	Enumerates many concrete capabilities — 'shared types (Y.Map, Y.Array, Y.Text)', 'transactions', 'y-protocols sync and awareness', 'y-indexeddb persistence', 'conflict resolution' — matching the multiple-specific-actions anchor.	3 / 3
Completeness	Explicitly states what it does and when to use it via the 'Use when mentioning ...' clause, satisfying both the what and the when.	3 / 3
Trigger Term Quality	Covers natural user phrasing broadly: 'Yjs', 'Y.Doc', 'CRDTs', 'collaborative editing', 'real-time sync', 'awareness', 'IndexeddbPersistence', 'Yjs providers' — the terms a user would actually say.	3 / 3
Distinctiveness Conflict Risk	Niche Yjs-specific triggers ('Y.Doc', 'IndexeddbPersistence', 'Yjs providers') make it unlikely to fire for unrelated skills.	3 / 3
	Total	12 / 12 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/yjs/SKILL.md
Commit: cb12bcc

Reviewed: 3 days ago

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