Name: webiny-api-cms-custom-field-type
Rating: 62.4 (1 reviews)
Author: webiny

webiny-api-cms-custom-field-type

How to implement a custom CMS field type that integrates with the model builder's fluent API. Covers extending DataFieldBuilder, composing validator interfaces, creating a FieldTypeFactory, registering via DI, and module augmentation for TypeScript autocomplete on the fields() registry.

Quality

73%

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Quality

Content

80%

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 reference with complete executable examples and well-organized sections, held back only by absent validation checkpoints in the workflow and no file-level progressive disclosure for the large inline API/validator catalogs.

Suggestions

Add an explicit verification step (e.g., confirm fields.slug() resolves and the type does not collide with built-ins) to lift workflow clarity.

Move the Available Validators and DataFieldBuilder API tables into a reference bundle file, referenced one level deep from the body, to improve progressive disclosure.

Dimension	Reasoning	Score
Conciseness	The body is dense and reference-style — tables, code, and key rules — with no padding explaining concepts Claude already knows; every section earns its tokens.	3 / 3
Actionability	Provides fully executable, copy-paste-ready TypeScript (builder interface, module augmentation, builder class, factory, registration) plus complete method/validator tables.	3 / 3
Workflow Clarity	The three-part structure and numbered 1–5 example give a clear sequence, but there are no explicit validation or verification checkpoints, keeping it below the top anchor.	2 / 3
Progressive Disclosure	Sections are well-organized, but the ~250-line body keeps all API/validator reference material inline with no bundle-file references to split it out, so it is not fully progressive.	2 / 3
	Total	10 / 12 Passed

Description

67%

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 specific, well-scoped description that names concrete actions and a clear niche, but it omits explicit "Use when…" trigger guidance and leans heavily on API jargon rather than natural user phrasing.

Suggestions

Add an explicit "Use when…" clause naming natural triggers (e.g., when the user wants to add a new field type to a Webiny CMS model, or needs a custom fluent field like fields.slug()).

Soften the jargon load by pairing API terms with plain-language equivalents a user might actually say.

Dimension	Reasoning	Score
Specificity	Lists multiple concrete actions — "extending DataFieldBuilder, composing validator interfaces, creating a FieldTypeFactory, registering via DI, and module augmentation" — matching the multi-action anchor.	3 / 3
Completeness	It clearly states what the skill does, but offers no "Use when…" trigger guidance, so per the judging guidelines completeness is capped at 2.	2 / 3
Trigger Term Quality	The natural phrase "custom CMS field type" is present, but the description is dominated by technical jargon (DataFieldBuilder, FieldTypeFactory, module augmentation, DI) and lacks common natural variations a user would say.	2 / 3
Distinctiveness Conflict Risk	The webiny-specific "custom CMS field type" niche with model-builder integration is highly distinct and unlikely to trigger for unrelated skills.	3 / 3
	Total	10 / 12 Passed

Validation

93%

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 — 15 / 16 Passed

Validation for skill structure

Criteria	Description	Result
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	15 / 16 Passed

Repository: webiny/webiny-js
Path: skills/user-skills/api/custom-field-type/SKILL.md
Commit: 484553b

Reviewed: about 12 hours ago

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