firefox-devtools-diagnose

firefox-devtools-diagnose is a skill for Claude Code from BAM-DevCrew/maxerviker-firefox-devtools-mcp. It costs 49 tokens per session (634 once invoked), scanned A, original, no licence file.

A troubleshooting guide for connecting Firefox DevTools to an agent. Firefox DevTools are the browser tools used to inspect pages and diagnose web problems.

In plain words
What is it for?
It is for diagnosing Firefox DevTools setup problems, failed connections, and reports that Firefox DevTools are not working in Cowork.
Why use it?
It helps identify why the Firefox DevTools connection is failing or why its tools are unavailable.

Skill for Claude Code

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

Part of the firefox-devtools-troubleshoot plugin — 1 skill 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/bam-devcrew/maxerviker-firefox-devtools-mcp/diagnose
Any agent
npx skills add BAM-DevCrew/maxerviker-firefox-devtools-mcp --skill diagnose
Clone the repo
git clone --depth 1 https://github.com/BAM-DevCrew/maxerviker-firefox-devtools-mcp

Made for: Claude Code.

Or install firefox-devtools-troubleshoot, the plugin that ships this one along with the rest of its 1 skill.

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 firefox-devtools-diagnose

README.md
[![agentmods](https://agentmods.dev/badge/skills/bam-devcrew/maxerviker-firefox-devtools-mcp/diagnose.svg)](https://agentmods.dev/skills/bam-devcrew/maxerviker-firefox-devtools-mcp/diagnose)
Your own site
<a href="https://agentmods.dev/skills/bam-devcrew/maxerviker-firefox-devtools-mcp/diagnose"><img src="https://agentmods.dev/badge/skills/bam-devcrew/maxerviker-firefox-devtools-mcp/diagnose.svg" alt="Measured on agentmods" height="20"></a>
Per session 49 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 634 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00049 $0.00634
Opus 5 $0.00024 $0.00317
Sonnet 5 $0.00010 $0.00127
Haiku 4.5 $0.00005 $0.00063

Measured 5d ago against content hash d2b85936a207, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

firefox-devtools-diagnose 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.

plugins/firefox-devtools-troubleshoot/skills/diagnose/SKILL.md · 42 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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 · 42 lines · 49 tokens per session scan A d2b85936a207

Subscribe to this mod's changes

firefox-devtools-diagnose is a skill published in the GitHub repository BAM-DevCrew/maxerviker-firefox-devtools-mcp (0 stars, last pushed 28d ago), with no licence file. It adds 49 tokens to every session and 634 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 2026-08-31.

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