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.
npx agentmods add skills/gabrielbryk/arc-devtools-mcp/troubleshootingnpx skills add gabrielbryk/arc-devtools-mcp --skill troubleshootinggit clone --depth 1 https://github.com/gabrielbryk/arc-devtools-mcpWrote 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.
[](https://agentmods.dev/skills/gabrielbryk/arc-devtools-mcp/troubleshooting)<a href="https://agentmods.dev/skills/gabrielbryk/arc-devtools-mcp/troubleshooting"><img src="https://agentmods.dev/badge/skills/gabrielbryk/arc-devtools-mcp/troubleshooting.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00040 | $0.01519 |
| Opus 5 | $0.00020 | $0.00759 |
| Sonnet 5 | $0.00008 | $0.00304 |
| Haiku 4.5 | $0.00004 | $0.00152 |
Grade B, and why
troubleshooting scanned grade B 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 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.
Reads MCP configurationmediumAgent snooping
mcp.json carries server URLs and auth tokens; reading it lets a mod discover and abuse other integrations.
Your first action should be to locate and read the MCP configuration file. Search for the following files in the user's workspace: `.mcp.json`, `gemini-extension.json`, `.claude/settings.json`, `.vscode/launch.json`, or This is a copy
100% identical to troubleshooting — 1 line differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 99 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Troubleshooting Wizard
You are acting as a troubleshooting wizard to help the user configure and fix their Chrome DevTools MCP server setup. When this skill is triggered (e.g., because list_pages, new_page, or navigate_page failed, or the server wouldn't start), follow this step-by-step diagnostic process:
Step 1: Find and Read Configuration
Your first action should be to locate and read the MCP configuration file. Search for the following files in the user's workspace: .mcp.json, gemini-extension.json, .claude/settings.json, .vscode/launch.json, or .gemini/settings.json.
If you find a configuration file, read and interpret it to identify potential issues such as:
- Incorrect arguments or flags.
- Missing environment variables.
- Usage of
--autoConnectin incompatible environments.
If you cannot find any of these files, only then should you ask the user to provide their configuration file content.
Step 2: Triage Common Connection Errors
Before reading documentation or suggesting configuration changes, check if the error message matches one of the following common patterns.
Error: Could not find DevToolsActivePort
This error is highly specific to the --autoConnect feature. It means the MCP server cannot find the file created by a running, debuggable Chrome instance. This is not a generic connection failure.
Your primary goal is to guide the user to ensure Chrome is running and properly configured. Do not immediately suggest switching to --browserUrl. Follow this exact sequence:
- Ask the user to confirm that the correct Chrome version (e.g., "Chrome Canary" if the error mentions it) is currently running.
- If the user confirms it is running, instruct them to enable remote debugging. Be very specific about the URL and the action: "Please open a new tab in Chrome, navigate to
chrome://inspect/#remote-debugging, and make sure the 'Enable remote debugging' checkbox is checked." - Once the user confirms both steps, your only next action should be to call the
list_pagestool. This is the simplest and safest way to verify if the connection is now successful. Do not retry the original, more complex command yet. - If
list_pagessucceeds, the problem is resolved. If it still fails with the same error, then you can proceed to the more advanced steps like suggesting--browserUrlor checking for sandboxing issues.
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.
- 5d ago First seen · 99 lines · 40 tokens per session scan B f7deca2af0ea
troubleshooting is a skill published in the GitHub repository gabrielbryk/arc-devtools-mcp (0 stars, last pushed 27d ago), licensed Apache-2.0. It adds 40 tokens to every session and 1,519 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it B with 1 finding (reads mcp configuration). It is 100% identical to troubleshooting, differing in 1 line, and is treated as a copy.
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