tests-purge-unneeded

tests-purge-unneeded is a skill for Claude Code, Codex from OutlineDriven/odin-codex-plugin. It costs 68 tokens per session (2,047 once invoked), scanned A, original, Apache-2.0.

A method for removing tests that do not catch real bugs, especially from older or recently refactored test suites.

In plain words
What is it for?
Use it to decide whether a test should stay by asking whether deleting it could let a real bug reach production, with mutation testing as an optional way to measure that value.
Why use it?
Unneeded tests make continuous integration slower and create noise without improving protection against failures.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: reads .claude/ paths.

Good fit Use it to decide whether a test should stay by asking whether deleting it could let a real bug reach production, with mutation testing as an optional way to measure that value.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/outlinedriven/odin-codex-plugin/tests-purge-unneeded
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 OutlineDriven/odin-codex-plugin --skill tests-purge-unneeded
Clone the repo
git clone --depth 1 https://github.com/OutlineDriven/odin-codex-plugin

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 tests-purge-unneeded

README.md
[![agentmods](https://agentmods.dev/badge/skills/outlinedriven/odin-codex-plugin/tests-purge-unneeded.svg)](https://agentmods.dev/skills/outlinedriven/odin-codex-plugin/tests-purge-unneeded)
Your own site
<a href="https://agentmods.dev/skills/outlinedriven/odin-codex-plugin/tests-purge-unneeded"><img src="https://agentmods.dev/badge/skills/outlinedriven/odin-codex-plugin/tests-purge-unneeded.svg" alt="Measured on agentmods" height="20"></a>
Per session 68 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,047 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.
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 5.1 $0.00068 $0.02047
Opus 5 $0.00034 $0.01024
Sonnet 5 $0.00014 $0.00409
Haiku 4.5 $0.00007 $0.00205

Measured 8d ago against content hash 1c8e724f4331, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

tests-purge-unneeded 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 8d 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

skills/tests-purge-unneeded/SKILL.md · 130 lines

How it starts

The opening of the file, as written. The whole thing — 130 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Purge unneeded tests — deletion as discipline

Tests are not assets. Tests are liabilities that pay rent by catching real bugs. Volume is not a quality signal — coverage percentage is not a quality signal — only the counterfactual matters: if I delete this test, can a real bug now reach prod? If the answer is no, the test is dead weight, and dead weight slows CI, breeds noise, and trains reviewers to ignore failures.

Modern insight (2025): TDD pairs with purge discipline. The same rigor that earns RED before GREEN earns deletion before keep — a test that cannot describe the bug it would catch should not exist. Mutation testing exposes which tests are actually load-bearing; the rest are cargo cult.

See python for pytest examples (dynamic-language carve-out). See typescript for jest/vitest examples (static-language redundancy). See rust for cargo test examples (compile-time-guaranteed redundancy). See keep-vs-delete-table for the language-agnostic decision rubric.


When to Apply

  • Reviewing a legacy test suite where CI takes minutes per run
  • Post-refactor sweeps — refactoring made some tests redundant; the refactor commit is the right place to delete them
  • PR review where the diff adds tests that assert structure the type system already guarantees
  • Onboarding to a codebase — flag suspicious patterns to surface for the original author
  • Mutation testing reports — tests that survive every mutation are not catching anything

When NOT to Apply

  • Standalone "delete tests" sweep PRs — these become unreviewable and bundle unrelated concerns. Deletions ride alongside the work that makes them safe to delete.
  • Behavior-change PRs where you have not separately confirmed the deletion is safe
  • Code paths under active migration where coverage is the only safety net
  • Any test whose failure mode you cannot articulate — if you cannot say what bug it would catch, you also cannot say it catches none

Read the full file on GitHub · 130 lines

Files

What ships with it

4 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. 8d ago First seen · 130 lines · 68 tokens per session scan A 1c8e724f4331

Subscribe to this mod's changes

tests-purge-unneeded is a skill published in the GitHub repository OutlineDriven/odin-codex-plugin (15 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 68 tokens to every session and 2,047 once invoked, about $0.0003 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 2026-08-30.

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