attach-primitive

Contract and invariants for `attach*` composition primitives in `packages/workspace` (side-effectful building blocks like attachIndexedDb, attachSqlite, attachBroadcastChannel, attachBunSqliteMaterializer, attachMarkdownMaterializer, openCollaboration), and when to use `create*` (pure construction) instead. Use when writing or reviewing an `attach*` or `create*` function, naming a new workspace primitive, composing inside a workspace builder, or deciding whether a primitive registers listeners at call time.

Quality

93%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Quality

Content

87%

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

A lean, highly actionable contract with executable examples and strong section organization; its only gap is the absence of explicit validation/verification checkpoints in the composition and destructive teardown flows.

Suggestions

Add an explicit verification checkpoint to the composition example, e.g. assert that child whenLoaded/whenConnected barriers have resolved before the bundle's whenReady is exposed.

Give the destructive wipe()/disposal flow a short ordered checklist with a verification step (e.g. confirm whenDisposed resolved and local storage cleared) so teardown has a feedback checkpoint.

Surface the gated startup order as a numbered sequence (1. createWorkspace -> 2. attachIndexedDb -> 3. openCollaboration(waitFor: idb.whenLoaded) -> 4. attachMarkdownMaterializer) in addition to the inline code, so the ordering is scannable.

Dimension	Reasoning	Score
Conciseness	The body is dense and project-specific, assuming Claude's competence (it never explains what a Y.Doc, IndexedDB, or FTS is) and earning its tokens with invariants and rationale Claude could not infer; there is no padded generic concept explanation.	3 / 3
Actionability	It gives executable call shapes ('attachIndexedDb(ydoc)', 'createWorkspace({ id, tables, kv })', 'attachMarkdownMaterializer(workspace, {...})') and a full copy-paste-style composition example, plus concrete invariants and anti-patterns rather than abstract direction.	3 / 3
Workflow Clarity	The composition sequence is present and explicitly gated via the waitFor convention, but there are no explicit validation checkpoints or feedback loops (e.g. verify barriers resolved before exposing the bundle, or confirm disposal completed), matching the anchor where sequence is present but checkpoints are missing.	2 / 3
Progressive Disclosure	No bundle files exist, but the body is well-organized into clearly headed sections (Naming, The shape, Invariants, Composition, waitFor, Anti-patterns, Reference implementations) with clearly signaled one-level-deep references to real repo files, avoiding nested or vague pointers.	3 / 3
	Total	11 / 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 highly specific, third-person description with explicit 'what' and 'when' guidance and concrete primitive names; it earns full marks across all four dimensions with no over-claims or fluff.

Dimension	Reasoning	Score
Specificity	Lists multiple concrete primitives ('attachIndexedDb, attachSqlite, attachBroadcastChannel, attachBunSqliteMaterializer, attachMarkdownMaterializer, openCollaboration') and a concrete decision ('when to use create* instead'), naming specific capabilities rather than vague abstractions.	3 / 3
Completeness	Explicitly answers what ('Contract and invariants for attach* composition primitives... and when to use create* instead') and when, via an explicit 'Use when...' clause, so it is not capped at 2.	3 / 3
Trigger Term Quality	The 'Use when writing or reviewing an attach* or create* function, naming a new workspace primitive, composing inside a workspace builder' clause covers the natural terms a developer in this codebase would actually say.	3 / 3
Distinctiveness Conflict Risk	The niche is sharply scoped to attach/create workspace primitives in packages/workspace with distinct triggers, making false activation for an unrelated skill very unlikely.	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/attach-primitive/SKILL.md
Commit: cb12bcc

Reviewed: 3 days ago

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