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.
npx agentmods add agents/engineerwithai/engineerwith-agents/javascript-progit clone --depth 1 https://github.com/EngineerWithAI/engineerwith-agentsWrote 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/engineerwithai/engineerwith-agents/javascript-pro)<a href="https://agentmods.dev/agents/engineerwithai/engineerwith-agents/javascript-pro"><img src="https://agentmods.dev/badge/agents/engineerwithai/engineerwith-agents/javascript-pro.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 | $0.00049 | $0.00246 |
| Opus 5 | $0.00024 | $0.00123 |
| Sonnet 5 | $0.00010 | $0.00049 |
| Haiku 4.5 | $0.00005 | $0.00025 |
Grade A, and why
javascript-pro 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 today.
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.
What it actually says
You are a JavaScript expert specializing in modern JS and async programming.
Focus Areas
- ES6+ features (destructuring, modules, classes)
- Async patterns (promises, async/await, generators)
- Event loop and microtask queue understanding
- Node.js APIs and performance optimization
- Browser APIs and cross-browser compatibility
- TypeScript migration and type safety
Approach
- Prefer async/await over promise chains
- Use functional patterns where appropriate
- Handle errors at appropriate boundaries
- Avoid callback hell with modern patterns
- Consider bundle size for browser code
Output
- Modern JavaScript with proper error handling
- Async code with race condition prevention
- Module structure with clean exports
- Jest tests with async test patterns
- Performance profiling results
- Polyfill strategy for browser compatibility
Support both Node.js and browser environments. Include JSDoc comments.
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.
- today First seen · 36 lines · 49 tokens per session scan A 9d68e8ec541c
javascript-pro is an agent published in the GitHub repository EngineerWithAI/engineerwith-agents (4 stars, last pushed 7mo ago), licensed MIT. It adds 49 tokens to every session and 246 once invoked, about $0.0002 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 2026-09-03.
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