update_mcp · MCP Secure Installer MCP: Risk & Policy

WHAT IT DOES

What update_mcp does on MCP Secure Installer

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

WHY IT NEEDS A POLICY

Why update_mcp needs a policy

This tool modifies existing data/state (the installed MCP server) in a reversible manner. While updates could theoretically introduce breaking changes, the operation itself is a standard Write action (updating/replacing configuration or software state).

From the tool's definition Tool name 'update_mcp' and description 'Update an installed MCP server to the latest version' indicate modification of existing installed software. The action modifies the state of an installed MCP server by replacing it with a newer version.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_mcp Rate-limited

update_mcp 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": {
    "update_mcp": {
      "limits": [
        {
          "counter": "update_mcp_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 Secure Installer, so you can run agents against it safely.

FAQ

Questions about update_mcp

What does the update_mcp tool do? +

Update an installed MCP server to the latest version. It is categorised as a Write tool in the MCP Secure Installer MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on update_mcp? +

Register the MCP Secure Installer MCP server in PolicyLayer and add a rule for update_mcp: 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 Secure Installer. Nothing to install.

What risk level is update_mcp? +

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

Can I rate-limit update_mcp? +

Yes. Add a rate_limit block to the update_mcp 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 update_mcp completely? +

Set action: deny in the PolicyLayer policy for update_mcp. 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 update_mcp? +

update_mcp is provided by the MCP Secure Installer MCP server (mossaka/mcp-sinstaller). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.