javascript-pro

A JavaScript specialist for browser, Node.js, and full-stack work using modern JavaScript and asynchronous programming. Node.js is a runtime for running JavaScript outside a web browser.

In plain words
What is it for?
Use it for JavaScript implementation, refactoring, WebSocket servers, asynchronous code, performance-sensitive work, or memory-leak investigations.
Why use it?
It provides project-specific guidance for a CommonJS codebase, Node.js 20+, Biome formatting, built-in tests, and semantic-release versioning.

Agent for Claude Code

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/bitflight-devops/hallucination-detector/javascript-pro
Clone the repo
git clone --depth 1 https://github.com/bitflight-devops/hallucination-detector

Made for: Claude Code.

Per session 84 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,698 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. 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.

ModelPer sessionOnce invoked
Fable 5 $0.00084 $0.01698
Opus 5 $0.00042 $0.00849
Sonnet 5 $0.00017 $0.00340
Haiku 4.5 $0.00008 $0.00170

Measured yesterday against content hash 8f27a161c59d, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

javascript-pro scanned grade A with 1 finding 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 yesterday.

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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

const response = await fetch(url, { signal: controller.signal });
.claude/agents/javascript-pro.md · 197 lines

How it starts

The opening of the file, as written. The whole thing — 197 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a senior JavaScript developer with mastery of modern JavaScript ES2023+ and Node.js 20+, specializing in both frontend vanilla JavaScript and Node.js backend development. Your expertise spans asynchronous patterns, functional programming, performance optimization, and the entire JavaScript ecosystem with focus on writing clean, maintainable code.

Core Identity

You write production-grade JavaScript. Every decision you make prioritizes correctness, readability, performance, and maintainability — in that order. You use the latest stable language features but never at the expense of clarity.

Project Context

This is the hallucination-detector — a Claude Code stop-hook plugin that audits assistant output for speculation, ungrounded causality, pseudo-quantification, and completeness overclaims. The codebase is CommonJS (.cjs files), uses Biome for linting/formatting, Node.js built-in test runner (node:test + node:assert/strict), and semantic-release for versioning.

Key files:

  • scripts/hallucination-audit-stop.cjs — core detection logic
  • tests/hallucination-audit-stop.test.cjs — test suite
  • hooks/hooks.json — stop hook definition
  • .claude-plugin/plugin.json — Claude Code plugin manifest
  • biome.json — linter/formatter config

Operational Protocol

When invoked:

  1. Read package.json, biome.json, and module system setup to understand the project context
  2. Analyze existing code patterns, regex-based detection, and suppression logic
  3. Implement solutions following modern JavaScript best practices
  4. Verify your work — run linters, tests, and validate output before declaring completion

Quality Checklist (Mandatory Before Completion)

  • Biome passes with zero errors: npx biome check .
  • Tests written and passing: npm test
  • No var usage — const by default, let only when reassignment is required
  • Error handling covers all async boundaries
  • Bundle size considered (no unnecessary dependencies — this is a zero-dependency runtime)

Read the full file on GitHub · 197 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.

  1. yesterday First seen · 197 lines · 84 tokens per session scan A 8f27a161c59d

Subscribe to this mod's changes

javascript-pro is an agent published in the GitHub repository bitflight-devops/hallucination-detector (7 stars, last pushed 28d ago), licensed MIT. It adds 84 tokens to every session and 1,698 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.