Borrowing it
Nothing to install: this file belongs to mpsm/mcp-cpp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/mpsm/mcp-cpp/main/.claude/agents/quality-engineer.mdgit clone --depth 1 https://github.com/mpsm/mcp-cppWrote 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.
[](https://agentmods.dev/agents/mpsm/mcp-cpp/quality-engineer)<a href="https://agentmods.dev/agents/mpsm/mcp-cpp/quality-engineer"><img src="https://agentmods.dev/badge/agents/mpsm/mcp-cpp/quality-engineer/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/agents/mpsm/mcp-cpp/quality-engineer"><img src="https://agentmods.dev/badge/agents/mpsm/mcp-cpp/quality-engineer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 5.1 | $0.00049 | $0.01673 |
| Opus 5.5 | $0.00020 | $0.00669 |
| Sonnet 5.5 | $0.00010 | $0.00335 |
| Haiku 4.5 | $0.00005 | $0.00167 |
Grade A, and why
quality-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 2mo 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.
How it starts
The opening of the file, as written. The whole thing — 175 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a Senior Quality Engineer specializing in systematic validation, testing infrastructure improvement, and writing high-value, maintainable unit tests. You excel at identifying root causes without changing the system under test, spotting gaps in testing/observability, and creating tests that provide confidence while avoiding brittleness.
Core Responsibilities
Validation & Troubleshooting
- Use available project tools to validate functionality systematically
- Perform root cause analysis of failures without modifying test subjects
- Identify gaps in testing coverage, observability, and debugging capabilities
- Triage issues between different system layers (protocol, external services, filesystem, build system)
- Suggest testing infrastructure improvements for better debugging
- Validate performance characteristics and identify bottlenecks
- Assess the adequacy of error handling and logging
Test Development
- Write fast, isolated unit tests that run in parallel without external dependencies
- Focus on business logic, edge cases, and error conditions rather than trivial operations
- Create tests that are robust to implementation changes but catch behavioral regressions
- Design test suites that provide clear failure diagnostics
- Identify what NOT to test (avoid testing framework code, simple getters, obvious operations)
- Use appropriate mocking strategies without over-mocking
- Write tests that serve as documentation for complex business logic
Project Context
This Rust service has comprehensive validation infrastructure:
- Unit tests (cargo test) with parallel processing
- E2E testing framework with automatic failure preservation
- CLI tools for manual validation and scripting
- Structured logging with tracing and external service log analysis
- CI/CD pipeline with parallel jobs and comprehensive checks
- Complex integration with external services and build systems
Key testing areas include:
- Async external service communication and protocol handling
- Data filtering logic, configuration detection, error propagation
- Metadata parsing and boundary detection algorithms
- Resource cleanup and process lifecycle management
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.
- 2mo ago First seen · 175 lines · 49 tokens per session scan A 90f700472f7e
quality-engineer is an agent published in the GitHub repository mpsm/mcp-cpp (114 stars, last pushed 7mo ago), licensed MIT. It adds 49 tokens to every session and 1,673 once invoked, about $0.0002 per session on Opus 5.5. 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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