PromptGuard MCP Server

Standalone Model Context Protocol server for PromptGuard — scan prompts for injection attacks, redact PII, and audit LLM SDK usage from any MCP-compatible client.

Installing the MCP Server

pip (recommended)

pip install promptguard-mcp-server

uvx (zero-install)

uvx promptguard-mcp-server

npx

npx @promptguard/mcp-server

Docker

docker pull abhijoysarkar/promptguard-mcp-server
docker run -e PROMPTGUARD_API_KEY=pg_xxx abhijoysarkar/promptguard-mcp-server

Homebrew (CLI)

brew tap promptguard/tap
brew install promptguard

Quick Start

1. Install

pip install promptguard-mcp-server

2. Configure your API key

export PROMPTGUARD_API_KEY="pg_sk_prod_YOUR_KEY"

Or skip this — the agent will call promptguard_auth automatically when needed.

3. Add to your MCP client

Cursor — add to .cursor/mcp.json:

{
  "mcpServers": {
    "promptguard": {
      "command": "promptguard-mcp-server",
      "args": []
    }
  }
}

Claude Desktop — add to claude_desktop_config.json:

{
  "mcpServers": {
    "promptguard": {
      "command": "promptguard-mcp-server",
      "args": []
    }
  }
}

Claude Code:

claude mcp add promptguard -- promptguard-mcp-server

Gemini CLI:

gemini mcp add -t stdio promptguard -- promptguard-mcp-server

VS Code Copilot — add to settings.json:

{
  "github.copilot.chat.mcp.servers": {
    "promptguard": {
      "command": "promptguard-mcp-server",
      "args": []
    }
  }
}

Transports

The server supports two transports:

Transport	Command	Default
stdio	promptguard-mcp-server	Yes
Streamable HTTP	promptguard-mcp-server --transport http	Port 8000

stdio (default)

Used by Cursor, Claude Desktop, VS Code, and most MCP clients. The server communicates via stdin/stdout using JSON-RPC 2.0.

promptguard-mcp-server

Streamable HTTP

Used for remote/shared deployments. The MCP endpoint is served at http://HOST:PORT/mcp.

promptguard-mcp-server --transport http --host 0.0.0.0 --port 9000

Docker

stdio mode

docker run -i --rm \
  -e PROMPTGUARD_API_KEY=pg_xxx \
  abhijoysarkar/promptguard-mcp-server

Streamable HTTP mode

docker run --rm -p 8000:8000 \
  -e PROMPTGUARD_API_KEY=pg_xxx \
  abhijoysarkar/promptguard-mcp-server \
  --transport http

Available Tools

Tool	Description	Auth Required
promptguard_auth	Authenticate with PromptGuard (opens dashboard or saves key)	No
promptguard_logout	Clear locally stored credentials	No
promptguard_scan_text	Scan text for prompt injection, jailbreaks, PII, toxic content	Yes
promptguard_scan_project	Scan a directory for unprotected LLM SDK usage	No
promptguard_redact	Redact PII from text (emails, phones, SSNs, credit cards)	Yes
promptguard_status	Check connection status, plan, and API version	No

Environment Variables

Variable	Default	Description
PROMPTGUARD_API_KEY	—	API key (starts with pg_sk_test_ or pg_sk_prod_)
PROMPTGUARD_API_URL	https://api.promptguard.co	API base URL (for self-hosted deployments)
TRANSPORT	stdio	Transport type when running via Docker
HOST	0.0.0.0	HTTP bind address
PORT	8000	HTTP port

When no environment variable is set, the server reads from ~/.promptguard/config.json (created by promptguard_auth).

Development

git clone https://github.com/acebot712/promptguard.git
cd promptguard/mcp-server

pip install -e .
promptguard-mcp-server

Building the Docker image

docker build -t abhijoysarkar/promptguard-mcp-server .

Running tests

echo '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{}}' | promptguard-mcp-server

Links

• Documentation
• Homepage
• Dashboard
• Issues