ui-console-debug

ui-console-debug is a skill for Claude Code, Codex from roarista/awesome-harness. It costs 50 tokens per session (665 once invoked), scanned A, original, MIT.

A browser-based debugging procedure for checking a web page in Chrome, including its error messages, network requests, and screenshot.

In plain words
What is it for?
Use it to investigate web pages that do not display correctly, are stuck, or show console errors. The procedure covers navigation, reloading, reading errors, checking requests, and taking screenshots.
Why use it?
It replaces guesswork about a broken or blank page with evidence from the browser itself, then repeats the checks after changes.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: reads .claude/ paths.

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/roarista/awesome-harness/ui-console-debug
Any agent
npx skills add roarista/awesome-harness --skill ui-console-debug
Clone the repo
git clone --depth 1 https://github.com/roarista/awesome-harness

Made for: Claude Code, Codex.

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 ui-console-debug

README.md
[![agentmods](https://agentmods.dev/badge/skills/roarista/awesome-harness/ui-console-debug.svg)](https://agentmods.dev/skills/roarista/awesome-harness/ui-console-debug)
Your own site
<a href="https://agentmods.dev/skills/roarista/awesome-harness/ui-console-debug"><img src="https://agentmods.dev/badge/skills/roarista/awesome-harness/ui-console-debug.svg" alt="Measured on agentmods" height="20"></a>
Per session 50 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 665 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 $0.00050 $0.00665
Opus 5 $0.00025 $0.00332
Sonnet 5 $0.00010 $0.00133
Haiku 4.5 $0.00005 $0.00067

Measured 5d ago against content hash 70f7cd17048d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

ui-console-debug 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 5d 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.

skills/ui-console-debug/SKILL.md · 49 lines

How it starts

The opening of the file, as written. The whole thing — 49 lines — stays where its author put it; the contents beside it link to each section on GitHub.

UI Console Debug Loop

Debug a web page the way a human does with F12, but automated through the claude-in-chrome MCP tools. Never guess at a UI bug from source alone — read the browser's own error first.

Preconditions

  • Load tools in ONE ToolSearch call: select:mcp__claude-in-chrome__tabs_context_mcp,mcp__claude-in-chrome__navigate,mcp__claude-in-chrome__read_console_messages,mcp__claude-in-chrome__computer,mcp__claude-in-chrome__read_network_requests
  • Call tabs_context_mcp first (createIfEmpty: true). Never reuse tab IDs from old sessions.

The loop

  1. Navigate to the page URL (or reuse the tab if Ro is already on it).
  2. Read console: read_console_messages with a pattern like error|Error|declared|undefined|failed|404. NOTE: tracking starts at first call — if messages look stale (old timestamps) or empty, hard-reload with computer key cmd+shift+r, wait 2-3s, read again.
  3. Screenshot (computer action screenshot) — visual state is a second, independent signal; a page can be error-free and still visually wrong.
  4. Diagnose from the REAL error text, not from expectations. Classic traps:
    • Two classic <script> files declaring the same top-level const → "Identifier X has already been declared" → wrap each file in an IIFE.
    • Stale cache → always hard reload (cmd+shift+r), never plain reload.
  5. Fix the source, node --check any edited JS, hard-reload, re-read console. Repeat until console shows zero errors.
  6. Verify visually with a final screenshot (save_to_disk: true so Ro gets the absolute path). If interaction matters (zoom, drag), actually perform it via computer (scroll/click/drag) and screenshot the result.
  7. For network issues (404 assets, CORS): read_network_requests.

Rules

Read the full file on GitHub · 49 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. 5d ago First seen · 49 lines · 50 tokens per session scan A 70f7cd17048d

Subscribe to this mod's changes

ui-console-debug is a skill published in the GitHub repository roarista/awesome-harness (1 stars, last pushed 10d ago), licensed MIT. It adds 50 tokens to every session and 665 once invoked, about $0.0003 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 2026-08-31.

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