Agent Guardrail MCP Server

Action-level governance for AI agents -- control what they DO, not what they SAY

Remote serverstreamable-httpPython

What is the Agent Guardrail MCP server?

Action-level governance for AI agents -- control what they DO, not what they SAY. Exposed over MCP by the agent guardrail mcp server, that capability becomes something an assistant can invoke while it works, not something you go and do afterwards.

What it actually does

AI agents are getting tool access. They can run shell commands, make API calls, read files, spend money. But most "guardrails" only filter what agents say — not what they do.

Adding it to your client

Being a remote server, there is no local install. You register the endpoint with your client, authorise it once, and the tools appear.

Configuration

You will need 4 environment variables: YOUR_ADMIN_KEY, BLOCKONOMICS_API_KEY, BLOCKONOMICS_WEBHOOK_SECRET, GUARDRAIL_ADMIN_KEY. The server will not start without them, which is usually why the tools fail to appear on a first run. Keep credentials in your client's env block or a secrets manager rather than in a file you might commit.

Caveats

  • Your data travels to the provider's service, so the usual questions apply about what you send and what they retain.
  • Missing credentials fail quietly in some clients — if no tools show up, check the environment block first.
  • MCP clients confirm each tool call by default. Leave that on until you have watched what the agent guardrail mcp server does with a few real requests.

When to reach for it

Plenty of developer tooling servers cover similar ground. The differences that matter in practice are scope of access and how much setup stands between you and a working tool call. It is maintained by JarvisOnM4; worth a glance at recent repository activity before you build anything load-bearing on it.

SyncDev reviews every entry in this directory against the project's own documentation before publishing, and revisits them as servers change.

How to install the Agent Guardrail MCP server

{
  "mcpServers": {
    "agent-guardrail": {
      "command": "uvx",
      "args": ["agent-guardrail"],
      "env": {
        "YOUR_ADMIN_KEY": "your-value",
        "BLOCKONOMICS_API_KEY": "your-value",
        "BLOCKONOMICS_WEBHOOK_SECRET": "your-value",
        "GUARDRAIL_ADMIN_KEY": "your-value"
      }
    }
  }
}

Add to claude_desktop_config.json, then restart Claude Desktop.

Configuration

VariableDescriptionRequired
YOUR_ADMIN_KEYCredential the server authenticates with.Yes
BLOCKONOMICS_API_KEYCredential the server authenticates with.Yes
BLOCKONOMICS_WEBHOOK_SECRETCredential the server authenticates with.Yes
GUARDRAIL_ADMIN_KEYCredential the server authenticates with.Yes

Frequently asked questions

It connects Agent Guardrail to MCP-compatible AI assistants such as Claude and Cursor. Instead of copying data back and forth by hand, the assistant works with Agent Guardrail directly.