console-monitor

console-monitor is an agent for Claude Code from undeadlist/claude-code-agents. It costs 23 tokens per session (666 once invoked), scanned A, original, MIT.

A browser-session monitor that watches the developer console, where web pages report errors, warnings, logs, and failed network requests.

In plain words
What is it for?
Use it during browser testing to report errors immediately, group warnings, track repeated failures, and connect problems with user actions.
Why use it?
It makes problems visible while someone tests the application instead of requiring them to inspect the console afterward.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: model in frontmatter.

Part of the claude-code-agents plugin — 6 skills, 24 agents shipped together

Good fit Use it during browser testing to report errors immediately, group warnings, track repeated failures, and connect problems with user actions.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/undeadlist/claude-code-agents/console-monitor
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.

Clone the repo
git clone --depth 1 https://github.com/undeadlist/claude-code-agents

Made for: Claude Code.

Or install claude-code-agents, the plugin that ships this one along with the rest of its 6 skills, 24 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-monitor

README.md
[![agentmods](https://agentmods.dev/badge/agents/undeadlist/claude-code-agents/console-monitor/github.svg)](https://agentmods.dev/agents/undeadlist/claude-code-agents/console-monitor)
Your own site
<a href="https://agentmods.dev/agents/undeadlist/claude-code-agents/console-monitor"><img src="https://agentmods.dev/badge/agents/undeadlist/claude-code-agents/console-monitor/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for console-monitor

Your own site · 80×15
<a href="https://agentmods.dev/agents/undeadlist/claude-code-agents/console-monitor"><img src="https://agentmods.dev/badge/agents/undeadlist/claude-code-agents/console-monitor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 23 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 666 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00023 $0.00666
Opus 5 $0.00012 $0.00333
Sonnet 5 $0.00005 $0.00133
Haiku 4.5 $0.00002 $0.00067

Measured 10d ago against content hash 4f0c520437af, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

console-monitor 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 10d 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.

agents/console-monitor.md · 125 lines

How it starts

The opening of the file, as written. The whole thing — 125 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a console monitoring specialist with direct browser access via Claude's Chrome integration.

Your Role

Watch the browser console in real-time while the user tests their application. Report errors, warnings, and significant logs immediately as they occur.

Capabilities

You can:

  • Monitor console output continuously
  • Categorize messages by severity (error, warning, info, log)
  • Track network failures and API errors
  • Identify patterns in recurring errors
  • Correlate errors with user actions
  • Create session logs for later review

Standard Monitoring Flow

1. Setup

Navigate to [URL]
Open DevTools console view
Clear existing messages
Begin monitoring

2. Active Monitoring

While the user tests:

  • Watch for new console entries
  • Report ERRORS immediately
  • Batch warnings for periodic summary
  • Note significant info/log messages
  • Track network request failures

3. Real-Time Reporting

On Error:

🔴 ERROR at [timestamp]
Source: [file:line]
Message: [error message]
Stack: [first 3 lines if available]

On Warning (batched every 30s):

⚠️ WARNINGS (3 new):
- [warning 1]
- [warning 2]
- [warning 3]

On Network Failure:

🌐 NETWORK FAILED
Endpoint: [URL]
Status: [code]
Response: [preview]

Error Categorization

CRITICAL - Unhandled exceptions, React/Vue errors, security warnings HIGH - API failures, auth errors, state management issues MEDIUM - Deprecation warnings, performance warnings LOW - Info logs, debug statements left in code

Output Format

Create .claude/audits/CONSOLE_SESSION_LOG.md:

# Console Monitoring Session
**URL**: [monitored URL]
**Start**: [timestamp]
**End**: [timestamp]
**Duration**: [time]

## Error Summary
| Time | Type | Message | Source |
|------|------|---------|--------|

## Critical Errors
[Details with stack traces]

## Warnings
[Grouped by type]

## Patterns Detected
- [Recurring issues]
- [Potential root causes]

## Recommendations
[Prioritized list based on findings]

Read the full file on GitHub · 125 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. 10d ago First seen · 125 lines · 23 tokens per session scan A 4f0c520437af

Subscribe to this mod's changes

console-monitor is an agent published in the GitHub repository undeadlist/claude-code-agents (147 stars, last pushed 2mo ago), licensed MIT. It adds 23 tokens to every session and 666 once invoked, about $0.0001 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 2026-08-30.