What is io.github.ExpertVagabond/guardrails?

AI Agent Guardrails MCP server - security layer

How do I install io.github.ExpertVagabond/guardrails?

Clone io.github.ExpertVagabond/guardrails from https://github.com/ExpertVagabond/guardrails-mcp-server.git and configure it as an MCP server in your client (Claude Desktop, Cursor, or VS Code).

Is io.github.ExpertVagabond/guardrails open source?

Yes, io.github.ExpertVagabond/guardrails is open source under the MIT license. Source code is available at https://github.com/ExpertVagabond/guardrails-mcp-server.git.

What category does io.github.ExpertVagabond/guardrails belong to?

io.github.ExpertVagabond/guardrails is listed under Developer Tools MCP servers on MCPFind.

io.github.ExpertVagabond/guardrails — MCP Server for Developer Tools

guardrails-mcp-server

[!License: MIT](https://opensource.org/licenses/MIT) [!MCP](https://modelcontextprotocol.io) [!Node.js](https://nodejs.org)

MCP server for AI agent security guardrails. Provides input validation, prompt injection detection, PII redaction, output filtering, policy enforcement, rate limiting, and comprehensive audit logging.

Tools

Tool	Description
`validate_input`	Validate and sanitize incoming requests through all guardrail checks
`filter_output`	Filter and redact sensitive data (PII, secrets, credentials) from responses
`check_policy`	Evaluate a request against security policies (RBAC, resource access, quotas)
`get_audit_logs`	Query the audit log with filtering by type, user, time range
`get_stats`	Get engine statistics including active users, block rate, request counts
`update_config`	Update guardrail configuration at runtime

Security Features

Prompt Injection Detection -- 12 regex patterns for jailbreak, DAN mode, system prompt override
PII Detection and Redaction -- SSN, credit card, email, phone, IP, API keys, AWS keys, JWT, passwords, private keys, connection strings
Malicious Code Blocking -- eval, exec, subprocess, child_process, shell injection
Policy Engine -- Block sensitive paths, dangerous tools, unauthenticated destructive ops, URL allowlist, maintenance windows
Rate Limiting -- Per-user sliding window (configurable requests/minute)
Audit Logging -- Timestamped events with metrics, log rotation, external handler support

Install

npm install

Configuration

{
  "mcpServers": {
    "guardrails": {
      "type": "stdio",
      "command": "node",
      "args": ["/path/to/guardrails-mcp-server/index.js"]
    }
  }
}

Project Structure

src/engine/GuardrailsEngine.js    # Core orchestration
src/validators/InputValidator.js   # Prompt injection and PII detection
src/filters/OutputFilter.js        # Redaction and harmful content blocking
src/policies/PolicyEngine.js       # RBAC, quotas, maintenance windows
src/audit/AuditLogger.js           # Event logging and metrics

License

MIT

Set up in your AI client

AI clientOperating system

Merge this template into ~/Library/Application Support/Claude/claude_desktop_config.json. Keep existing servers. Add any arguments, credentials, and permissions required by the maintainer; this template has not been install-tested.

json

{
  "mcpServers": {
    "io-github-expertvagabond-guardrails": {
      "command": "npx",
      "args": [
        "-y",
        "guardrails-mcp-server"
      ]
    }
  }
}

Restart Claude Desktop completely for changes to take effect. Confirm the server appears connected in the client’s tool list, then try a read-only example from its documentation.

Claude Desktop setup reference

Compatible MCP Clients

io.github.ExpertVagabond/guardrails works with any MCP-compatible client. Copy the config snippet from the Configuration section above and add it to the file shown for your client, then restart the application.

Claude Desktop~/Library/Application Support/Claude/claude_desktop_config.jsonRestart Claude Desktop completely for changes to take effect.

Cursor~/.cursor/mcp.jsonRestart Cursor for changes to take effect.

VS Code.vscode/mcp.jsonReload VS Code window for changes to take effect.

Windsurf~/.codeium/windsurf/mcp_config.jsonRestart Windsurf for changes to take effect.

Claude Code.mcp.jsonSave at the project root, then start Claude Code in that project and review the MCP server approval prompt. Keep real credentials out of shared files.

io.github.ExpertVagabond/guardrails