update_group · Groupme MCP: Risk & Policy

WHAT IT DOES

What update_group does on Groupme

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

WHY IT NEEDS A POLICY

Why update_group needs a policy

The 'update_group' tool modifies group configuration or properties, which is a reversible Write operation. It does not delete data (Destructive), does not execute arbitrary code (Execute), and has no financial implications. The moderate severity reflects that an agent could misuse this to alter group settings in ways that affect multiple users, but the impact is limited to a single group and can be undone.

From the tool's definition Tool name is 'update_group' on a GroupMe API server that manages groups, messages, members, and bots. The name 'update' indicates modification of group data (settings, metadata, etc.).

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_group Rate-limited

update_group 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_group": {
      "limits": [
        {
          "counter": "update_group_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 Groupme, so you can run agents against it safely.

FAQ

Questions about update_group

What does the update_group tool do? +

update_group. It is categorised as a Write tool in the Groupme 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_group? +

Register the Groupme MCP server in PolicyLayer and add a rule for update_group: 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 Groupme. Nothing to install.

What risk level is update_group? +

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

Can I rate-limit update_group? +

Yes. Add a rate_limit block to the update_group 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_group completely? +

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

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