console-debugging

console-debugging is a skill for Claude Code from jpoutrin/product-forge. It costs 37 tokens per session (1,371 once invoked), scanned A, original, MIT.

A debugging guide for reading JavaScript errors, warnings, and other messages in a web browser’s developer console.

In plain words
What is it for?
Use it to examine runtime errors, network and security messages, deprecations, and debugging logs in Chrome DevTools.
Why use it?
It helps turn noisy console output into likely causes and next steps when a browser-based application behaves unexpectedly.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the product-design plugin — 43 skills, 8 agents shipped together

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 skills/jpoutrin/product-forge/console-debugging
Any agent
npx skills add jpoutrin/product-forge --skill console-debugging
Clone the repo
git clone --depth 1 https://github.com/jpoutrin/product-forge

Made for: Claude Code.

Or install product-design, the plugin that ships this one along with the rest of its 43 skills, 8 agents.

Wrote 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.

agentmods badge for console-debugging

README.md
[![agentmods](https://agentmods.dev/badge/skills/jpoutrin/product-forge/console-debugging.svg)](https://agentmods.dev/skills/jpoutrin/product-forge/console-debugging)
Your own site
<a href="https://agentmods.dev/skills/jpoutrin/product-forge/console-debugging"><img src="https://agentmods.dev/badge/skills/jpoutrin/product-forge/console-debugging.svg" alt="Measured on agentmods" height="20"></a>
Per session 37 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,371 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. 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 5.1 $0.00037 $0.01371
Opus 5 $0.00018 $0.00685
Sonnet 5 $0.00007 $0.00274
Haiku 4.5 $0.00004 $0.00137

Measured 2d ago against content hash b096ce06e119, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

console-debugging 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 2d 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.

plugins/product-design/skills/console-debugging/SKILL.md · 200 lines

How it starts

The opening of the file, as written. The whole thing — 200 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Console Debugging Skill

Systematic approach to analyzing browser console messages using Chrome DevTools MCP.

Console Message Categories

Error Messages (Highest Priority)

Type Example Typical Cause
JavaScript Error Uncaught TypeError: Cannot read property 'x' of undefined Null reference
Network Error Failed to load resource: net::ERR_CONNECTION_REFUSED API unavailable
CORS Error Access-Control-Allow-Origin Backend configuration
CSP Error Content Security Policy Security restriction
Syntax Error SyntaxError: Unexpected token Invalid JavaScript
Reference Error ReferenceError: x is not defined Undefined variable

Warning Messages (Medium Priority)

Type Example Action
Deprecation 'componentWillMount' is deprecated Plan migration
Performance Long task took 200ms Optimize
Security Insecure form submission Fix HTTPS
Mixed Content Mixed Content: loading HTTP on HTTPS Update resource URLs

Info/Log Messages (Context)

Type Purpose
Debug output Developer console.log statements
Library info Framework initialization messages
Analytics Tracking events
State changes Application state updates

Analysis Workflow

1. Collect Console Messages

Use Chrome DevTools MCP to list all console messages:

Tool: mcp__chrome-devtools__list_console_messages
Parameters: { "level": "error" }  // or "warning", "info", "debug"

2. Filter by Severity

Start with errors, then warnings:

  1. Errors first - These break functionality
  2. Warnings second - These indicate problems
  3. Info last - These provide context

3. Group by Source

Categorize errors by their origin:

  • Application code - Your own JavaScript
  • Third-party libraries - External dependencies
  • Browser/extension - Not your code
  • Network - API/resource failures

Read the full file on GitHub · 200 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. 2d ago First seen · 200 lines · 37 tokens per session scan A b096ce06e119

Subscribe to this mod's changes

console-debugging is a skill published in the GitHub repository jpoutrin/product-forge (15 stars, last pushed 6mo ago), licensed MIT. It adds 37 tokens to every session and 1,371 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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