shift-left-testing

shift-left-testing is a skill for Claude Code, Codex from petrkindlmann/qa-skills. It costs 149 tokens per session (5,693 once invoked), scanned A, original, MIT.

A guide for involving quality checks earlier while building software. It covers developer-and-tester collaboration, TDD (writing a failing test, making it pass, then improving the code), review checklists, and team maturity.

In plain words
What is it for?
Use it to plan developer/tester collaboration, run Three Amigos requirement sessions, decide whether to use TDD, review pull requests for test quality, and assess how early your team handles quality.
Why use it?
It helps prevent testers from finding problems only after development is supposedly finished. It gives teams shared steps for discussing requirements, testing code, and defining when work is complete.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

not rated 113repo +7 2mo ago A scan Socket: passSnyk: passSkillSpector: pass 149 tokens original MIT

Good fit Use it to plan developer/tester collaboration, run Three Amigos requirement sessions, decide whether to use TDD, review pull requests for test quality, and assess how early your team handles quality.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/petrkindlmann/qa-skills/shift-left-testing
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 petrkindlmann/qa-skills --skill shift-left-testing
Clone the repo
git clone --depth 1 https://github.com/petrkindlmann/qa-skills

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 shift-left-testing

README.md
[![agentmods](https://agentmods.dev/badge/skills/petrkindlmann/qa-skills/shift-left-testing.svg)](https://agentmods.dev/skills/petrkindlmann/qa-skills/shift-left-testing)
Your own site
<a href="https://agentmods.dev/skills/petrkindlmann/qa-skills/shift-left-testing"><img src="https://agentmods.dev/badge/skills/petrkindlmann/qa-skills/shift-left-testing.svg" alt="Measured on agentmods" height="20"></a>
Per session 149 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,693 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
  • Socket pass 11 May 2026
  • Snyk pass 11 May 2026
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00149 $0.05693
Opus 5 $0.00075 $0.02847
Sonnet 5 $0.00030 $0.01139
Haiku 4.5 $0.00015 $0.00569

Measured 7d ago against content hash 818a0cd2c207, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

shift-left-testing 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 7d 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/shift-left-testing/SKILL.md · 400 lines

How it starts

The opening of the file, as written. The whole thing — 400 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Quick Route

Situation Go to
QA only sees features after dev is "done" Dev/QA Pairing → QA in Sprint Planning
Need a pre-dev requirements conversation Dev/QA Pairing → Three Amigos Sessions
Deciding whether to TDD this work TDD Facilitation → When TDD vs. Test-After
Reviewing a PR for test quality PR Review Checklist
Reviewing an AI-generated/AI-using PR PR Review Checklist → When the Change Is AI-Generated
"Where is my team and what's next?" Shift-Left Maturity Model

Discovery Questions

Check .agents/qa-project-context.md first — if it exists, use it (team composition, dev/QA workflow, sprint structure, quality goals) and skip anything answered there.

Current Dev/QA Workflow

  1. When does QA first see a feature? After PR is raised? After merge to staging? Only when a bug appears? The answer reveals how far right your quality currently sits.

  2. Who writes tests, and when? Developers only? QA only after dev is "done"? Both but on different timelines? Understanding current ownership is essential before changing it.

  3. How are requirements communicated? Written specs? Verbal handoffs? Figma links with no acceptance criteria? Ambiguous requirements are the #1 source of defects that shift-left prevents.

  4. Is there interest in TDD? Has the team tried it before? Did it stick or collapse? Understanding past attempts prevents repeating failed approaches.

  5. What does the PR review process look like? Who reviews? Is testability a review criterion? Are tests required before merge? PR review is the lowest-friction place to introduce quality checks.

Read the full file on GitHub · 400 lines

Files

What ships with it

2 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. 7d ago First seen · 400 lines · 149 tokens per session scan A 818a0cd2c207

Subscribe to this mod's changes

shift-left-testing is a skill published in the GitHub repository petrkindlmann/qa-skills (113 stars, last pushed 2mo ago), licensed MIT. It adds 149 tokens to every session and 5,693 once invoked, about $0.0007 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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