MCP Server Auditor

Name: MCP Server Auditor
Author: GuardBee

by GuardBeeversion 0.4.1i★ –iRuns on your computer

Registry nameio.github.GuardBee/mcp-server-auditor

Install

Overview

Description from the maker (original English)

Scans MCP server tool definitions for excessive agency, injection sinks, hardcoded secrets

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

User voiceiNo reviews yetReviews open together with accounts in a later step
Our basic checksi1 of 1 passedChecked from public information; code not scanned yet
UsageiNot measured yet★ –

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

Connection: Runs on your computer
Transport: stdio
Category: Other

Install

Pick the AI app you use, then copy the settings.

Before you install

Basic checks: 1 of 1 passed
Runs on your computer with your user’s permissions (files, network, apps).
The registry lists no key to fill in.

You need

npmNode.js installed (for the npx command)

Which app do you use?

ClaudeClaude CodeCursorVS CodeChatGPT

Pick your app above. We remember it, so next time the button says “Install in …”.

Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json

{
  "mcpServers": {
    "auditor": {
      "command": "npx",
      "args": [
        "-y",
        "@guardbee/mcp-server-auditor"
      ]
    }
  }
}

Run this in your terminal

claude mcp add auditor -- npx -y @guardbee/mcp-server-auditor

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "auditor": {
      "command": "npx",
      "args": [
        "-y",
        "@guardbee/mcp-server-auditor"
      ]
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "auditor": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@guardbee/mcp-server-auditor"
      ]
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

This one runs on your computer, and ChatGPT can only connect to servers on the internet. Pick another app.

Your choice stays on this device in a cookie; no account needed.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Runs on your computer; the tool list appears in your AI app after you install it.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026

✓ Pass
Maker matches the repo
The registry name was verified with the GitHub account GuardBee, which owns the repo
… Not checked yet
Still maintained
We have not read this repo from GitHub yet
… Not checked yet
Has a licence
We have not read this repo from GitHub yet
– Not applicable
Endpoint responds
This one runs on your computer; there is no internet endpoint
– Not applicable
Sign-in with OAuth
Runs on your computer and uses local settings instead
… Not checked yet
No hidden instructions in tool descriptions
Runs on your computer; we can only read tool lists from internet endpoints

Compared with others in Otheri

More stars than 0% of the other 32602 servers in this category
Published to the registry more recently than 82% of the other 32602 servers in this category
Basic checks equal to or better than 100% of the other 32602 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is MCP Server Auditor safe?

It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

The registry does not list a required key, though some servers ask you to sign in on first use.

Does it run on my computer or in the cloud?

It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).

Is it still maintained?

The GitHub repo last changed –, and the latest version (0.4.1) reached the registry 7 days ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Node.js on your computer.

What can I use instead?

In the same category: Spec Driven Development, Remote Desktop Commander, Rystic

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

Spec Driven Development

by formulahendry

MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.

Runs on your computer★ 440MITUpdated 14 months ago

Install

Remote Desktop Commander

by desktop-commander

Remote Desktop Commander: use files, terminal and processes on your own computers from any AI app.

Runs in the cloud★ 211Updated 2 days ago

Install

Rystic

by Rystic-Inc

Start, seed, clock, inspect and diff Rystic API simulators from your agent.

Runs on your computerUpdated today

Install

README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

@guardbee/mcp-server-auditor

An MCP (Model Context Protocol) server that scans other MCP servers' tool definitions for insecure patterns.

While ai-code-scanner looks at general LLM/AI integration code, this package specifically looks at an MCP server itself: how privileged a tool defined via server.tool(...) is, how loose its parameters are, which dangerous sinks (shell/filesystem/HTTP/SQL) its handler passes tool input into directly. The MCP ecosystem is growing fast, but there's no common tool yet for auditing these servers' security.

Telemetry is off by default. With GUARDBEE_TELEMETRY=1 it sends the server, tool, success, duration and short parameter values such as a file path; longer strings and fields like content, token or password are replaced with a placeholder. See @guardbee/mcp-telemetry.

Claude ──► mcp-server-auditor ──► An MCP server's source code

│ ├─ Excessive agency (execSync(input.command), a tool named "run_shell") ├─ Unsafe input (fetch(input.url) → SSRF, SQL string interpolation) ├─ Loose schema (a parameter typed z.any()/z.unknown()) ├─ Secrets exposure (a hardcoded API key in a schema default, the entire process.env) └─ Network exposure (wildcard CORS)

Features

10 patterns, 5 categories — excessive-agency, unsafe-input, loose-schema, secrets-exposure, network-exposure
Python and Go servers: tool input followed from the tool definition (FastMCP parameters, low-level arguments, go-sdk typed args, mcp-go request.RequireString(...)) through plain assignments into shell, file write/delete, HTTP and SQL calls
Every finding includes why it's risky and what to do about it (recommendation) — not just "found it"
SARIF 2.1.0 output — CI/CD integration (GitHub Code Scanning, etc.)
Config file support via guardbee.yml
A positive and a negative (false-positive) test for every pattern, with vulnerable and clean Python and Go fixtures

Quick Start

Claude Desktop / MCP Client

"mcpServers": { "guardbee-mcp-server-auditor": { "command": "npx", "args": ["-y", "@guardbee/mcp-server-auditor"] } } }

CLI (CI/CD)

npx @guardbee/mcp-server-auditor scan ./src --fail-on=high --format=sarif > results.sarif

MCP Tools

Tool	Description
`scan_text`	Scans a given text/code snippet
`scan_file`	Scans a single file
`scan_directory`	Recursively scans a directory (`node_modules`, `.git`, `dist` skipped automatically)
`list_patterns`	Lists all supported patterns by category

Detected Patterns

Category	Pattern	Severity	OWASP	What it means
excessive-agency	`shell_exec_from_tool_input`	critical	MCP05:2025	A tool handler passes tool input directly into a shell call like `execSync`/`spawn`
excessive-agency	`eval_of_tool_input`	critical	MCP05:2025	Tool input is executed as code via `eval()`/`new Function()`
excessive-agency	`unrestricted_shell_tool_name`	high	MCP05:2025	A tool name (`run_shell`, `execute_sql`, etc.) implies shell/SQL execution directly
unsafe-input	`fs_write_from_raw_tool_input`	high		A path from tool input flows into a file write/delete call with no validation (path traversal)
unsafe-input	`ssrf_fetch_from_tool_input`	high		A URL from tool input flows directly into `fetch`/`axios` with no allowlist (SSRF)
unsafe-input	`sql_injection_via_tool_input`	critical	MCP05:2025	Tool input is interpolated into a SQL string via a template literal
loose-schema	`overly_permissive_tool_schema`	medium	A tool parameter is typed `z.any()`/`z.unknown()` — accepts anything
secrets-exposure	`hardcoded_secret_in_tool_schema`	critical	A credential-shaped schema field's default value is a hardcoded literal
secrets-exposure	`full_env_exposed_to_tool_caller`	critical	The entire `process.env` is spread/stringified/returned (not one named variable)
network-exposure	`permissive_cors_on_server`	medium	Wildcard CORS (`Access-Control-Allow-Origin: *`) or `cors()` with no options

Python and Go

Python (.py) and Go (.go) files also get a tool-input flow check. The tool's input names come from its definition, are followed through plain assignments in the handler (command = f"du {directory}"), and a finding is reported when one reaches a sink call:

Pattern	Severity	Sinks
`python_shell_from_tool_input`	critical	`subprocess.`, `os.system`, `os.popen`, `asyncio.create_subprocess_`
`python_eval_of_tool_input`	critical	`eval`, `exec`
`python_fs_write_from_tool_input`	high	`open(..., "w"/"a"/"x")`, `os.remove`/`rename`/…, `shutil.rmtree`/`move`, `Path(...).write_text`/`unlink`
`python_ssrf_from_tool_input`	high	`requests.`, `httpx.`, `client.get(...)`, `urlopen` (URL argument)
`python_sql_injection_via_tool_input`	critical	`cursor.execute(f"...{x}...")`, `%` / `.format` / `+`
`go_shell_from_tool_input`	critical (`sh -c`), high (argument list)	`exec.Command`, `exec.CommandContext`
`go_fs_write_from_tool_input`	high	`os.WriteFile`, `os.Remove`, `os.RemoveAll`, `os.Rename`, `os.Create`, `os.OpenFile` for writing
`go_ssrf_from_tool_input`	high	`http.Get`/`Post`/`NewRequest…`, `client.Get`
`go_sql_injection_via_tool_input`	critical	`db.Query…`/`Exec…` with `fmt.Sprintf` or `+`

File findings are skipped when the handler checks the path against a base directory (is_relative_to, commonpath, .parents, filepath.IsLocal, filepath.Rel, strings.HasPrefix), and HTTP findings when it checks a host allowlist. Tools named run_shell, execute_sql etc. are reported for both languages. Rust, Java, Kotlin, C# and other languages get the language-neutral patterns only.

These are heuristic findings — a static text-pattern scan, not a full AST/type analysis. Designed for a low false-positive rate, but every finding should still be reviewed manually.

Configuration (`guardbee.yml`)

mcp-server-auditor:

".test.ts"
"fixtures/"

Development

npm run build

npm test

License

MIT — GuardBee

Feedback

Questions, ideas, or a false positive? Start a thread in GitHub Discussions or open an issue. If GuardBee is useful to you, a ⭐ on the repository helps others find it.

MCP Server Auditor

Overview

PopNx MCP’s three pillars

What you can do with it

Install

Before you install

What it can do

Basic checksi

Maker matches the repo

Still maintained

Has a licence

Endpoint responds

Sign-in with OAuth

No hidden instructions in tool descriptions

Compared with others in Otheri

Common questions

Alternatives

Spec Driven Development

Remote Desktop Commander

Rystic

README from the maker

@guardbee/mcp-server-auditor

Features

Quick Start

Claude Desktop / MCP Client

CLI (CI/CD)

MCP Tools

Detected Patterns

Python and Go

Configuration (guardbee.yml)

Development

License

Feedback

Configuration (`guardbee.yml`)