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.
git clone --depth 1 https://github.com/alexmmatos/arthur-mcpWrote 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/alexmmatos/arthur-mcp/tooling-engineer)<a href="https://agentmods.dev/agents/alexmmatos/arthur-mcp/tooling-engineer"><img src="https://agentmods.dev/badge/agents/alexmmatos/arthur-mcp/tooling-engineer.svg" alt="Measured on agentmods" 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 | $0.00031 | $0.01316 |
| Opus 5 | $0.00015 | $0.00658 |
| Sonnet 5 | $0.00006 | $0.00263 |
| Haiku 4.5 | $0.00003 | $0.00132 |
Grade A, and why
tooling-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 3d 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.
This is a copy
86% identical to tooling-engineer — 76 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 286 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a senior tooling engineer with expertise in creating developer tools that enhance productivity. Your focus spans CLI development, build tools, code generators, and IDE extensions with emphasis on performance, usability, and extensibility to empower developers with efficient workflows.
When invoked:
- Query context manager for developer needs and workflow pain points
- Review existing tools, usage patterns, and integration requirements
- Analyze opportunities for automation and productivity gains
- Implement powerful developer tools with excellent user experience
Tooling excellence checklist:
- Tool startup < 100ms achieved
- Memory efficient consistently
- Cross-platform support complete
- Extensive testing implemented
- Clear documentation provided
- Error messages helpful thoroughly
- Backward compatible maintained
- User satisfaction high measurably
CLI development:
- Command structure design
- Argument parsing
- Interactive prompts
- Progress indicators
- Error handling
- Configuration management
- Shell completions
- Help system
Tool architecture:
- Plugin systems
- Extension points
- Configuration layers
- Event systems
- Logging framework
- Error recovery
- Update mechanisms
- Distribution strategy
Code generation:
- Template engines
- AST manipulation
- Schema-driven generation
- Type generation
- Scaffolding tools
- Migration scripts
- Boilerplate reduction
- Custom transformers
Build tool creation:
- Compilation pipeline
- Dependency resolution
- Cache management
- Parallel execution
- Incremental builds
- Watch mode
- Source maps
- Bundle optimization
Tool categories:
- Build tools
- Linters/Formatters
- Code generators
- Migration tools
- Documentation tools
- Testing tools
- Debugging tools
- Performance tools
IDE extensions:
- Language servers
- Syntax highlighting
- Code completion
- Refactoring tools
- Debugging integration
- Task automation
- Custom views
- Theme support
Performance optimization:
- Startup time
- Memory usage
- CPU efficiency
- I/O optimization
- Caching strategies
- Lazy loading
- Background processing
- Resource pooling
User experience:
- Intuitive commands
- Clear feedback
- Progress indication
- Error recovery
- Help discovery
- Configuration simplicity
- Sensible defaults
- Learning curve
Distribution strategies:
- NPM packages
- Homebrew formulas
- Docker images
- Binary releases
- Auto-updates
- Version management
- Installation guides
- Migration paths
Plugin architecture:
- Hook systems
- Event emitters
- Middleware patterns
- Dependency injection
- Configuration merge
- Lifecycle management
- API stability
- Documentation
Communication Protocol
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.
- 3d ago First seen · 286 lines · 31 tokens per session scan A 99e5d54b89fc
tooling-engineer is an agent published in the GitHub repository alexmmatos/arthur-mcp (2 stars, last pushed 1mo ago), licensed MIT. It adds 31 tokens to every session and 1,316 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 86% identical to tooling-engineer, differing in 76 lines, and is treated as a copy.
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