pathguard-mcp

PathGuard MCP lets MCP-compatible AI agents check crypto transactions for scams and mistakes directly in conversation. It supports local MCP clients such as Claude Desktop, Claude Code, Gemini CLI, Grok CLI, Cursor, and Codex, plus remote Streamable HTTP deployments.

Listed on the official MCP Registry as org.cieltech.pathguard/pathguard.

The MCP server is a thin wrapper around the authenticated PathGuard API. Your PathGuard API key remains the credential used by the server and should never be exposed to an AI client or committed to source control.

Install

The package is currently installed directly from this public repository and is not published to PyPI yet.

git clone https://github.com/Utee/pathguard-mcp.git
cd pathguard-mcp
python -m pip install .

For development, use an editable install:

python -m pip install -e .

Requires Python 3.10+ and mcp >= 2.0.

Get an API key

Create a PathGuard account and API key from the PathGuard API documentation.

Keep your API key private. Do not commit it to GitHub or expose it in browser-side code.

Test locally

After installation, verify the MCP server starts with the default stdio transport:

export PATHGUARD_API_KEY=pg_your_key_here
pathguard-mcp

The stdio process waits for MCP messages from the client. This is normal; desktop and CLI MCP clients manage the process for you.

To point the MCP server at a local PathGuard API instead of production:

export PATHGUARD_API_KEY=pg_your_test_key
export PATHGUARD_API_BASE=http://localhost:8000
pathguard-mcp

Configure local MCP clients

Install this package wherever the client runs, then give the server your PathGuard API key. The examples below use the installed pathguard-mcp command. If it is not on your PATH, replace it with the full executable path.

Claude Desktop

Add this to your Claude Desktop config (claude_desktop_config.json):

{
  "mcpServers": {
    "pathguard": {
      "command": "pathguard-mcp",
      "env": {
        "PATHGUARD_API_KEY": "pg_your_key_here"
      }
    }
  }
}

Restart Claude Desktop, and Claude will have access to PathGuard's tools automatically.

Claude Code

claude mcp add --transport stdio pathguard -- \
  pathguard-mcp

Set PATHGUARD_API_KEY in the environment that starts Claude Code. Alternatively, use Claude Code's MCP configuration to pass that variable explicitly.

Gemini CLI

Add this entry to ~/.gemini/settings.json for a user-wide setup, or .gemini/settings.json in a project:

{
  "mcpServers": {
    "pathguard": {
      "command": "pathguard-mcp",
      "env": {
        "PATHGUARD_API_KEY": "pg_your_key_here"
      }
    }
  }
}

Or add it from the command line after exporting your key:

export PATHGUARD_API_KEY=pg_your_key_here
gemini mcp add --scope user pathguard pathguard-mcp

Grok CLI

After exporting your key, add the local stdio server:

export PATHGUARD_API_KEY=pg_your_key_here
grok mcp add pathguard -- pathguard-mcp

To store the configuration manually in ~/.grok/config.toml, use:

[mcp_servers.pathguard]
command = "pathguard-mcp"
env = { PATHGUARD_API_KEY = "${PATHGUARD_API_KEY}" }

Codex, Cursor, VS Code, and other local MCP clients

Use the same stdio server definition as the Claude Desktop example: command pathguard-mcp, no arguments, and PATHGUARD_API_KEY in its environment. The exact configuration-file location and UI differ by client; the MCP server settings are the same.

Configure remote clients

For browser-based MCP clients such as ChatGPT or Grok, deploy PathGuard MCP with Streamable HTTP behind HTTPS. Never put a PathGuard API key in client-side browser configuration.

Start the HTTP server locally or in your deployment environment:

export PATHGUARD_API_KEY=pg_your_key_here
pathguard-mcp --transport streamable-http --host 0.0.0.0 --port 8000 \
  --allowed-host mcp.example.com

The MCP endpoint is http://<host>:8000/mcp. In production, publish it as a protected HTTPS URL such as https://mcp.example.com/mcp.

Environment-based deployment

The server also supports deployment configuration through environment variables:

PATHGUARD_API_KEY=pg_your_key_here
PATHGUARD_API_BASE=https://pathguard-v2.up.railway.app
PATHGUARD_MCP_TRANSPORT=streamable-http
PATHGUARD_MCP_HOST=0.0.0.0
PATHGUARD_MCP_PORT=8000
PATHGUARD_MCP_ALLOWED_HOSTS=mcp.example.com

PATHGUARD_MCP_ALLOWED_HOSTS accepts a comma-separated list. PORT is used when PATHGUARD_MCP_PORT is not set.

ChatGPT

In a ChatGPT workspace with Developer Mode enabled, create a custom MCP app, provide your public https://.../mcp endpoint, scan its tools, and save or publish it as appropriate for your workspace. ChatGPT connects to remote MCP servers for this use case.

Grok web

Use Grok's custom connector flow and provide your public https://.../mcp endpoint. The server must be reachable over HTTPS.

Security notes

• Keep PATHGUARD_API_KEY server-side and private.
• Use HTTPS for remote deployments.
• Restrict allowed hosts for Streamable HTTP deployments.
• The MCP server authenticates to PathGuard with the configured API key; it does not provide separate per-MCP-user authentication.
• Do not commit API keys, production credentials, or local .env files.

Available tools

Tool	What it does
check_transaction	Scan a single transaction for scam addresses, clipboard-hijack patterns, and typo mistakes
check_transactions_batch	Scan up to 1,000 transactions in one call
report_scam_address	Flag an address as a scam (community reporting)
get_usage_status	Check your current plan, quota, and usage this month

Full API reference

See the PathGuard API documentation for complete endpoint documentation, rate limits, and flag meanings. This MCP server is a thin wrapper over the same API.