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ActionGuard Protocol Inspector Agent

by lsendelversion 1.0.0i★ –iRuns in the cloud
Registry nameio.github.lsendel/actionguard

Install

Overview

Description from the maker (original English)

Diff and poisoning detection for MCP servers: catch schema drift and prompt poisoning.

PopNx MCP’s three pillars

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

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.

Install

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

Before you install

  • Basic checks: 1 of 1 passed
  • Runs on the maker’s server: what you ask it goes through their server.
  • The registry lists no key to fill in.

You need

Which app do you use?

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

Works in Claude on the web, desktop and mobile:

  1. Open Settings → Connectors
  2. Press Add custom connector
  3. Paste the address below and press Add
  4. If it asks you to sign in, sign in with the maker
SettingsConnectors1+ Add2https://…3
https://actionguard.ai/mcp

Run this in your terminal

claude mcp add --transport http actionguard https://actionguard.ai/mcp

Open in Cursor

Or copy the settings yourself

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

{
  "mcpServers": {
    "actionguard": {
      "url": "https://actionguard.ai/mcp"
    }
  }
}

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": {
    "actionguard": {
      "type": "http",
      "url": "https://actionguard.ai/mcp"
    }
  }
}

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.

ChatGPT connects only to servers on the internet:

  1. Open ChatGPT on the web → Settings → Connectors (Apps)
  2. Press Create or Add (some plans need Developer mode under Advanced first)
  3. Paste the address below, give it a name and save
  4. If it asks you to sign in, sign in with the maker
SettingsConnectors1+ Create2https://…3
https://actionguard.ai/mcp

Menu names can differ slightly by plan and over time.

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

We have not read this server’s tool list yet; we check endpoints in rotation.

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 lsendel, 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 checked yet

    Endpoint responds

    Not checked yet; we check endpoints in rotation

  • … Not checked yet

    Sign-in with OAuth

    Not checked yet; we check endpoints in rotation

  • … Not checked yet

    No hidden instructions in tool descriptions

    Not checked yet; we read the tool list when we check the endpoint

Compared with others in Otheri

  • More stars than 0% of the other 32545 servers in this category
  • Published to the registry more recently than 70% of the other 32545 servers in this category
  • Basic checks equal to or better than 100% of the other 32545 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 ActionGuard Protocol Inspector Agent 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 in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.

Is it still maintained?

The GitHub repo last changed –, and the latest version (1.0.0) reached the registry 16 days ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.

What can I use instead?

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

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 yesterday
Install

Python MCP

by Files-com

Local-only Python MCP server for the Files.com API.

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.

ActionGuard.ai

Drift and poisoning detection for MCP servers.

*"SSL Labs for MCP servers. Know when your tools change, not just when they go down."*

Diff detection for MCP tools: catch silent schema drift and poisoned tool descriptions before your autonomous agents run them.

Live Production Services

Quickstart

1. GitHub Actions CI Gate

Block breaking changes and unannounced schema mutations before they hit production:

name: CI

on: [pull_request]

jobs: verify-agent-tools: runs-on: ubuntu-latest steps:

  • name: Verify Upstream MCP Tools uses: lsendel/actionguard@v1 with: target_url: 'https://github.mcp.modelcontextprotocol.io/mcp' pinned_hash: '81d36f5215b689d6f100cfe77096fbe8d113c304c0dd8374d69a84678fb69415'
2. Zero-Trust Runtime Gateway Proxy ("Cloudflare for MCP")

Route agent tool calls through ActionGuard's edge firewall to terminate drifted tools with HTTP 423 Locked:

{

"mcpServers": { "weather": { "command": "npx", "args": [ "-y", "@modelcontextprotocol/server-weather", "--proxy", "https://actionguard.ai/proxy/v1?target=https%3A%2F%2Fapi.weather.com%2Fmcp&pin=a1b2c3d4..." ] } } }

3. Embed Live Status Badges in Your Repository

Show real-time verification and protocol compliance on your MCP server's GitHub repository.

Markdown (Native SVG)
[![ActionGuard Verified](https://actionguard.ai/badge/<your-domain-or-slug>.svg)](https://actionguard.ai/servers/<your-domain-or-slug>)
Shields.io Endpoint
[![ActionGuard Verified](https://img.shields.io/endpoint?url=https%3A%2F%2Factionguard.ai%2Fbadge%2F<your-domain-or-slug>.json)](https://actionguard.ai/servers/<your-domain-or-slug>)
  • Domain Verified Badge: Gold (#f59e0b) badge ⭐ A • Domain Owner displayed when domain ownership is claimed via DNS TXT or .well-known/actionguard-verification.
  • Reliability Grades: Dynamic color coding based on cryptographic dual-hash baseline and 5-stage protocol inspection (A+, A, B, C, D, F).
Claude Desktop & Cursor (claude_desktop_config.json)
{

"mcpServers": { "github": { "url": "https://actionguard.ai/v1/proxy?target=https://github.mcp.modelcontextprotocol.io/mcp&pin=81d36f5215b689d6f100cfe77096fbe8d113c304c0dd8374d69a84678fb69415" } } }

Python (LangChain / CrewAI / httpx)
import httpx

GATEWAY = "https://actionguard.ai/v1/proxy" TARGET = "https://github.mcp.modelcontextprotocol.io/mcp" PIN = "81d36f5215b689d6f100cfe77096fbe8d113c304c0dd8374d69a84678fb69415"

Requests fail with 423 Locked if upstream schema drifts or tool is poisoned

client = httpx.Client(base_url=f"{GATEWAY}?target={TARGET}&pin={PIN}")

3. Run as an MCP Server (Claude Desktop, Cursor, Glama)

You can run ActionGuard natively as a tool inside any MCP client:

Stdio Mode (Claude Desktop claude_desktop_config.json)
{

"mcpServers": { "actionguard": { "command": "npx", "args": ["-y", "@actionguard/cli", "mcp"] } } }

Streamable HTTP Mode
{

"mcpServers": { "actionguard": { "url": "https://actionguard.ai/mcp" } } }

4. CLI Quick Run
# Run 5-stage live protocol audit against any MCP or A2A endpoint

npx @actionguard/cli inspect https://api.myservice.com/mcp

Compile single actionguard.json to MCP server.json, A2A agent-card.json, and DNS-AID records

npx @actionguard/cli compile ./actionguard.json

Local CI check

npx @actionguard/cli check https://api.myservice.com/mcp --pin

Core Product Pillars

  1. The 5-Stage Live Inspector ("SSL Labs for Agents"): Zero-signup diagnostic tool running live edge probes against MCP and A2A endpoints, returning an A+ to F scorecard and instant copy-paste fixes.
  2. Dual-Hash Integrity Engine: Distinct cryptographic fingerprints for JSON Schemas (schema_sha256) versus tool descriptions (descriptions_sha256) to catch silent prompt mutations.
  3. Enterprise Dependency Watchlist: Automated 15-minute edge monitoring with instant multi-channel alerts (Slack Block Kit, Discord Embeds, Email via Resend, and signed Webhooks).
  4. Self-Serve Domain Proof (DNS-AID): Cryptographic domain verification via DNS TXT records or well-known challenge files to earn the Gold "⭐ Domain Verified" badge.
  5. Zero-Trust Runtime Firewall: Low-latency proxy (<15ms) that blocks execution before poisoned or drifted payloads reach your LLM.

Infrastructure Architecture

Built entirely on the Cloudflare edge stack for global sub-50ms latency:

  • Cloudflare Workers: Edge probing engine, public API, zero-trust proxy, and dynamic SVG badges.
  • Cloudflare D1: High-performance relational edge database for accounts, catalog, subscriptions, and API keys.
  • Cloudflare R2: Content-addressed, immutable storage for historical snapshot payloads, raw schemas, and audit logs.
  • Continuous Monitoring: 15-minute cron trigger with automatic drift detection and Resend email / Slack dispatch.

Monorepo Packages

├── packages/

│ ├── core/ # @actionguard/core — Dual-hash, linter, compiler, and probes │ └── cli/ # @actionguard/cli — actionguard command line tool └── apps/ └── worker/ # Cloudflare Worker — Web Inspector, API, proxy, and D1/R2 storage

Documentation

  • Product Requirements Document (PRD)
  • Protocol Specifications & Mappings
  • System Architecture & Data Model
  • Step-by-Step Implementation Plan
  • Hacker News Show HN Submission
  • Product Hunt & Twitter Launch Kit

License

MIT © ActionGuard.ai

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