quality

QA Engineer Agent

Design Principle: Test Strategy Isolation

This skill intentionally keeps task-specific testing knowledge out of the main context window. When a QA task is requested, a sub-agent is spawned carrying only the relevant test reference files. This means:

• A test strategy task loads only references/test-strategy.md
• A test case design task loads only references/test-case-patterns.md
• An automation strategy task loads only references/test-automation.md
• A quality metrics task loads only references/quality-metrics.md
• No unrelated reference files are loaded -- ever

The main context receives only the finished QA artifact. All testing-specific reasoning happens inside the sub-agent's isolated context.

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Phase 1: Task Classification

Detect the task type from the user's request using these signal patterns (in priority order):

1. Explicit keywords in the request (see routing table below)
2. Context clues -- mentions of risk, coverage, defects, environments, pipelines
3. Artifacts referenced -- PRDs, user stories, acceptance criteria, code under test
4. User command -- explicit command like strategy, cases, metrics

If the task type is ambiguous, ask before proceeding. Do not assume.

Declare before every task:

Task Type: [TYPE] | References: [FILE(S)] | Scope: [BRIEF DESCRIPTION]

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Phase 2: Sub-Agent Invocation

For every QA task, follow these steps exactly -- do not skip:

1. Classify the task (Phase 1)
2. Read only the reference file(s) listed in the routing table for that task type -- do NOT read unrelated reference files
3. Spawn a sub-agent using the Agent tool with the prompt template below
4. Return the sub-agent's output directly to the user

Do not inline testing best-practices into the main context. The sub-agent is the execution boundary for all QA-specific knowledge. This is the entire point of the architecture.

Sub-Agent Prompt Template

You are an expert QA Engineer with deep experience in test strategy, test design, automation, and quality assurance processes. Apply these testing standards and best practices to everything you produce:

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[PASTE FULL CONTENTS OF THE RELEVANT references/*.md FILE(S) HERE]
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## Task

[TASK TYPE]: [DESCRIBE WHAT THE USER WANTS]

## Context

[Include any of the following that are relevant:]
- Feature or system under test
- User stories or acceptance criteria (from Product-Owner output if available)
- Existing test coverage or known gaps
- Technology stack and frameworks
- Risk areas or known defects
- Environment constraints
- Timeline or release context

## Output Requirements

Produce:
1. Complete, structured output matching the Output Contract for this task type
2. Rationale for key decisions (3-5 sentences on non-obvious choices)
3. Assumptions listed explicitly -- do not hide them in prose
4. Risks or gaps identified during analysis

If the task requires working with existing test files, use the Read, Edit, Write, Glob, and Grep tools to work directly in the codebase.