wp-mutate

A testing skill for WordPress plugins and themes that changes code in controlled ways to see whether tests detect the changes. This technique is called mutation testing.

In plain words
What is it for?
Use it with Pest or Infection for PHP, or StrykerJS for JavaScript, to find surviving mutants and improve WordPress test coverage.
Why use it?
It reveals tests that pass but fail to catch realistic code defects by examining surviving mutations.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/soderlind/wordpress-agent-plugin/wp-mutate
Any agent
npx skills add soderlind/wordpress-agent-plugin --skill wp-mutate
Clone the repo
git clone --depth 1 https://github.com/soderlind/wordpress-agent-plugin

Made for: Claude Code, Codex.

Per session 45 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,653 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00045 $0.04653
Opus 5 $0.00023 $0.02327
Sonnet 5 $0.00009 $0.00931
Haiku 4.5 $0.00005 $0.00465

Measured yesterday against content hash 096da4f8f37b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

wp-mutate 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 yesterday.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/detect_mutation_setup.mjs), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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/wp-mutate/SKILL.md · 364 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Files

What ships with it

5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. yesterday First seen · 364 lines · 45 tokens per session scan A 096da4f8f37b

Subscribe to this mod's changes

wp-mutate is a skill published in the GitHub repository soderlind/wordpress-agent-plugin (2 stars, last pushed 4d ago), with no licence file. It adds 45 tokens to every session and 4,653 once invoked, about $0.0002 per session on Opus 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 2026-08-31.

Related

Other skills, from other repositories

elementor-v3-builder

Stonewright Elementor V3 builder for native-first implementation from Figma, screenshots, images, or briefs, plus pages, widgets, Loop Grid, templates, kit styles, responsive edits, and safe batch mutations. Use whenever a task reads, plans, builds, or repairs an Elementor V3 page or template.

cosmincraciun97/stonewright-wp-mcp · 68 tokens

gutenberg-fse-builder

Stonewright Gutenberg and FSE builder. Inserts/updates blocks, manages theme.json global styles, FSE templates, template parts, and synced patterns.

cosmincraciun97/stonewright-wp-mcp · 37 tokens

agent-operating-rules

Permanent product operating rules for every Stonewright agent: responsive device tabs, separate verification tabs, Figma section isolation, breakpoint isolation, native-first styling, fastest safe interface, verified learning, single-target environment, no ad-hoc plugins, HTTP-first automation, and Elementor native…

cosmincraciun97/stonewright-wp-mcp · 70 tokens

blocksy-build-page

Use when building Blocksy pages with live block schemas, theme chrome tokens, and the Gutenberg finalizer.

cosmincraciun97/stonewright-wp-mcp · 26 tokens

design-to-wordpress

Stonewright Figma/image/brief → DesignEvidence → native plan → Elementor / Gutenberg / FSE apply → agent-owned Playwright verification loop.

cosmincraciun97/stonewright-wp-mcp · 34 tokens

generateblocks-build-page

Use when building pages with GenerateBlocks, live generateblocks/ schemas, and GeneratePress chrome when that theme is active.

cosmincraciun97/stonewright-wp-mcp · 29 tokens