write-tests

write-tests is a skill for Claude Code, Codex from greglas75/zuvo. It costs 87 tokens per session (17,384 once invoked), scanned A, original, MIT.

A test-writing workflow for adding tests to existing production code, handling one file at a time and checking whether the tests cover the file's public behavior.

In plain words
What is it for?
Use it to add or improve tests for existing files, either by naming a file, choosing a directory, or discovering uncovered files automatically.
Why use it?
It helps find untested code and provides checks that test coverage is complete rather than relying on the writer's judgment.

Skill for Claude CodeCodex

Part of the zuvo plugin — 56 skills, 48 agents, 5 hooks shipped together

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/greglas75/zuvo/write-tests
Any agent
npx skills add greglas75/zuvo --skill write-tests
Clone the repo
git clone --depth 1 https://github.com/greglas75/zuvo

Made for: Claude Code, Codex.

Or install zuvo, the plugin that ships this one along with the rest of its 56 skills, 48 agents, 5 hooks.

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 write-tests

README.md
[![agentmods](https://agentmods.dev/badge/skills/greglas75/zuvo/write-tests.svg)](https://agentmods.dev/skills/greglas75/zuvo/write-tests)
Your own site
<a href="https://agentmods.dev/skills/greglas75/zuvo/write-tests"><img src="https://agentmods.dev/badge/skills/greglas75/zuvo/write-tests.svg" alt="Measured on agentmods" height="20"></a>
Per session 87 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 17,384 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original 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 $0.00087 $0.17384
Opus 5 $0.00044 $0.08692
Sonnet 5 $0.00017 $0.03477
Haiku 4.5 $0.00009 $0.01738

Measured yesterday against content hash 83da2c2e14a3, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

write-tests 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.

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/write-tests/SKILL.md · 856 lines

How it starts

The opening of the file, as written. The whole thing — 856 lines — stays where its author put it; the contents beside it link to each section on GitHub.

zuvo:write-tests — Single-File Test Pipeline

Generate high-quality tests for production code. Each file goes through the full pipeline individually — no batching of files or pipeline steps, no skipping verification in normal mode, no skipping the coverage gate or audit.

The pipeline's spine is inventory-first + executable proof: the public surface is enumerated and FROZEN before the first test is written, and the only authority on coverage completeness is scripts/test-coverage-gate.py — a program, not the writer's own claim.

Scope: Existing production files with missing or partial test coverage. Out of scope: New feature tests (use zuvo:build), mass anti-pattern repair (use zuvo:fix-tests), audit without writing (use zuvo:test-audit).

Argument Parsing

Input Behavior
[file.ts] Write tests for one production file
[directory/] Write tests for all production files in the directory
auto Discover uncovered files, process one at a time until done
--dry-run Run Phase 0 + Step 1 for all files, print plan, stop
--no-cache Re-run discovery/classification from scratch: ignore any cached CodeSift index answer and any previously built queue for this run
--resume <basename> Resume ONE file from its persisted checkpoint: load contracts/<basename>.coverage.json + contracts/<basename>.contract.md, verify production_sha256 against the file on disk (mismatch → refuse and demand re-inventory — the existing hash rule), take classification from the contract (skip Phase 0.5/Step 1 re-derivation), then jump by state: manifest inventory + contract present → Step 2; final → Step 3; final with Q-scores synced → Step 3.3
--resume-run <ledger> Resume an auto-mode queue from its run ledger (see Auto-mode context boundary): reload run-level facts + remaining queue, continue with the next file in a clean window

--no-cache forces Step 7's queue build to re-derive from a fresh scan rather than reusing a queue computed earlier in the session. (It used to promise clearing a "project-profile cache" that no step in this skill ever reads or writes — a dead flag until 2026-08-02.)

Read the full file on GitHub · 856 lines

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 · 856 lines · 87 tokens per session scan A 83da2c2e14a3

Subscribe to this mod's changes

write-tests is a skill published in the GitHub repository greglas75/zuvo (6 stars, last pushed yesterday), licensed MIT. It adds 87 tokens to every session and 17,384 once invoked, about $0.0004 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 2026-09-03.

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