shorten_url · MCP-Server MCP: Risk & Policy

WHAT IT DOES

What shorten_url does on MCP-Server

AI agents use shorten_url to create or update resources in MCP-Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your MCP-Server environment.

WHY IT NEEDS A POLICY

Why shorten_url needs a policy

This tool creates a new shortened URL entry (a mapping from a short alias to a long URL), which is a reversible write operation. It does not execute code, delete data, or involve financial transactions. The blast radius is low since misuse would at worst create unwanted short URLs.

From the tool's definition 'Shorten a URL using multiple services. Supports custom aliases and collections.'

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

shorten_url Rate-limited

shorten_url stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "shorten_url": {
      "limits": [
        {
          "counter": "shorten_url_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches MCP-Server, so you can run agents against it safely.

FAQ

Questions about shorten_url

What does the shorten_url tool do? +

Shorten a URL using multiple services. Supports custom aliases and collections. It is categorised as a Write tool in the MCP-Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on shorten_url? +

Register the MCP-Server MCP server in PolicyLayer and add a rule for shorten_url: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches MCP-Server. Nothing to install.

What risk level is shorten_url? +

shorten_url is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit shorten_url? +

Yes. Add a rate_limit block to the shorten_url rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block shorten_url completely? +

Set action: deny in the PolicyLayer policy for shorten_url. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides shorten_url? +

shorten_url is provided by the MCP-Server MCP server (surbhimotghare/mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.