webiny-api-cms-custom-field-type

webiny-api-cms-custom-field-type is a skill for Claude Code, Codex from webiny/webiny-js. It costs 60 tokens per session (2,551 once invoked), scanned A, original, no licence file.

A Webiny CMS guide for building a custom field type and adding it to the model builder's field registry.

In plain words
What is it for?
Use it to create custom CMS fields, define their validation rules, register their factories, and add autocomplete support to the fields API.
Why use it?
It explains the parts needed for validation, dependency registration, and TypeScript support when the built-in field types are not enough.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit Use it to create custom CMS fields, define their validation rules, register their factories, and add autocomplete support to the fields API.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/webiny/webiny-js/custom-field-type
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add webiny/webiny-js --skill custom-field-type
Clone the repo
git clone --depth 1 https://github.com/webiny/webiny-js

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for webiny-api-cms-custom-field-type

README.md
[![agentmods](https://agentmods.dev/badge/skills/webiny/webiny-js/custom-field-type/github.svg)](https://agentmods.dev/skills/webiny/webiny-js/custom-field-type)
Your own site
<a href="https://agentmods.dev/skills/webiny/webiny-js/custom-field-type"><img src="https://agentmods.dev/badge/skills/webiny/webiny-js/custom-field-type/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for webiny-api-cms-custom-field-type

Your own site · 80×15
<a href="https://agentmods.dev/skills/webiny/webiny-js/custom-field-type"><img src="https://agentmods.dev/badge/skills/webiny/webiny-js/custom-field-type.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 60 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,551 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin unknown No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00060 $0.02551
Opus 5.5 $0.00024 $0.01020
Sonnet 5.5 $0.00012 $0.00510
Haiku 4.5 $0.00006 $0.00255

Measured 1mo ago against content hash a1eba8d4515f, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

webiny-api-cms-custom-field-type scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/user-skills/api/custom-field-type/SKILL.md · 263 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 1mo ago First seen · 263 lines · 60 tokens per session scan A a1eba8d4515f

Subscribe to this mod's changes

webiny-api-cms-custom-field-type is a skill published in the GitHub repository webiny/webiny-js (8,047 stars, last pushed 2d ago), with no licence file. It adds 60 tokens to every session and 2,551 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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