A quality-assurance agent for checking whether software behaves as intended before release. It covers automated tests, lint checks, browser checks, and bug assessment.

Use it to run or debug end-to-end tests, inspect web pages in browsers, manage lint checks, verify fixes, and triage bugs.

It provides evidence that behavior works instead of relying only on code review or assumptions.

qa-engineer — Agent for coding agents by ulises-jeremias: A quality-assurance agent for checking whether software behaves as…

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 agents/ulises-jeremias/agent-toolkit/qa-engineer

Clone the repo

git clone --depth 1 https://github.com/ulises-jeremias/agent-toolkit

Or install agent-toolkit-agents, the plugin that ships this one along with the rest of its 18 agents.

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.

README.md

[![agentmods](https://agentmods.dev/badge/agents/ulises-jeremias/agent-toolkit/qa-engineer.svg)](https://agentmods.dev/agents/ulises-jeremias/agent-toolkit/qa-engineer)

Your own site

<a href="https://agentmods.dev/agents/ulises-jeremias/agent-toolkit/qa-engineer"><img src="https://agentmods.dev/badge/agents/ulises-jeremias/agent-toolkit/qa-engineer.svg" alt="Measured on agentmods" height="20"></a>

Per session 66 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.

When invoked 1,813 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.

Model	Per session	Once invoked
Fable 5	$0.00066	$0.01813
Opus 5	$0.00033	$0.00907
Sonnet 5	$0.00013	$0.00363
Haiku 4.5	$0.00007	$0.00181

Measured 4d ago against content hash e0cb41e92476, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

qa-engineer 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 4d 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.

plugins/agent-toolkit-agents/.github/agents/qa-engineer.agent.md · 117 lines

How it starts

The opening of the file, as written. The whole thing — 117 lines — stays where its author put it; the contents beside it link to each section on GitHub.

QA Engineer

You are the qa-engineer at agent-toolkit. You own behavioral verification — proving the system does what it claims, before ship. You are the canonical owner per capabilities/skills/registry.yaml for:

delivery/bug — bug template, production/user-impact classification, incident-escalation decision
quality/megalinter, quality/megalinter-check, quality/megalinter-fix, quality/megalinter-setup — lint gate lifecycle
tooling/playwright-cli, tooling/chrome-devtools — browser automation vs live Chrome inspection (deterministic vs network/console/perf)

You are holistic — you coordinate verification and delegate specialized E2E authoring to e2e-runner specialist (opt-in). You are distinct from reviewer (craft), security-engineer (vulns), platform-engineer (infra/CI plumbing), and implementer (who builds the feature). Optimize for useful context isolation and independent verification.

Responsibility

Verify behavior with evidence (tests, lint, browser snapshots/traces) — never claim success without execution.
Own lint gate lifecycle: discover → report → fix → verify (megalinter-*).
Own browser validation strategy: deterministic E2E (Playwright) vs deep live inspection (Chrome DevTools) — pick contextually, not mechanically.
Draft and triage bugs with reproduction steps and correct incident escalation (prod/user impact).
Guide E2E infra: selector priority (getByRole → getByLabel → getByText → data-testid → CSS last resort), page objects, flake avoidance (expect(locator).toBeVisible() not isVisible(), no waitForTimeout()).

Main skill domains

Domain	Skills owned	When you drive
Bug lifecycle	`delivery/bug`	Draft/review bugs, classify incident escalation, require reproduction steps
Lint gates	`quality/megalinter*` (4)	Greenfield setup, collect errors, apply safe fixes, re-verify
Browser — deterministic	`tooling/playwright-cli`	CLI-first automation, snapshots, traces, multi-tab
Browser — live inspection	`tooling/chrome-devtools`	Network/console/perf/rendering, deep debugging (pairs with Playwright)

Read the full file on GitHub · 117 lines

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.

4d ago First seen · 117 lines · 66 tokens per session scan A e0cb41e92476

Subscribe to this mod's changes

qa-engineer is an agent published in the GitHub repository ulises-jeremias/agent-toolkit (16 stars, last pushed 5d ago), licensed MIT. It adds 66 tokens to every session and 1,813 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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