PromptGuard
Harden agent and LLM apps by scanning prompts for injection, redacting PII, and auditing SDK usage from any MCP client.
Overview
PromptGuard Security is a MCP server for the Ship phase that scans prompts for injection, redacts PII, and audits LLM SDK usage from any MCP client.
What is this MCP server?
- stdio MCP server for injection detection on prompts
- PII redaction suitable for logging and agent transcripts
- LLM SDK usage auditing from any MCP-compatible client
- Shipped on PyPI, npm (@promptguard/mcp-server), and OCI Docker image 1.0.0
- PROMPTGUARD_API_KEY required (pg_sk_test_ or pg_sk_prod_ prefixes)
- Version 1.0.0
- 3 distribution channels: PyPI, npm, OCI Docker
- stdio transport only in registry
What problem does it solve?
Builders shipping agent features worry that user prompts and tool chains will leak PII or get hijacked by injection—and lack a quick guardrail in the IDE.
Who is it for?
Solo builders adding LLM endpoints, RAG, or tool-using agents who want PromptGuard checks inside their existing MCP workflow.
Skip if: Teams needing full WAF, SOC2 evidence packs, or security review with no API key budget or no LLM surface in the product.
What do I get? / Deliverables
With PromptGuard wired via stdio MCP, your agent can call security checks so risky prompts and sensitive data are caught before production traffic.
- Runnable PromptGuard MCP tools for injection scan, PII redaction, and SDK audit
- Configurable API URL for self-hosted PromptGuard backends
- Repeatable security checks callable from agent sessions
Recommended MCP Servers
Journey fit
How it compares
LLM prompt security MCP, not a general dependency vulnerability scanner or code review skill.
Common Questions / FAQ
Who is PromptGuard Security MCP for?
Developers shipping AI-powered apps and agents who need injection scanning, PII handling, and SDK audits without leaving their MCP setup.
When should I use PromptGuard Security MCP?
Use it in ship (and operate) whenever user-generated or retrieved text flows into models, tools, or logs in production-bound code.
How do I add PromptGuard Security to my agent?
Install promptguard-mcp-server from PyPI, @promptguard/mcp-server from npm, or the OCI image, set PROMPTGUARD_API_KEY, and register the stdio server in your MCP client config.