group_add_users · ArcGIS MCP: Risk & Policy

WHAT IT DOES

What group_add_users does on ArcGIS MCP

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

WHY IT NEEDS A POLICY

Why group_add_users needs a policy

This tool creates/modifies group membership relationships reversibly. Users can be removed from groups later, so it is not destructive. The action affects access control and group composition within ArcGIS, which could have moderate impact if misused by an agent (e.g., adding unauthorized users to sensitive groups), but does not directly execute code, delete data, or move money.

From the tool's definition Tool description explicitly states "OPERACIÓN DE ESCRITURA" (Write Operation). The name 'group_add_users' indicates it modifies group membership by adding users to a group.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

group_add_users Rate-limited

group_add_users 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": {
    "group_add_users": {
      "limits": [
        {
          "counter": "group_add_users_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 ArcGIS MCP, so you can run agents against it safely.

FAQ

Questions about group_add_users

What does the group_add_users tool do? +

Agrega usuarios a un grupo. OPERACIÓN DE ESCRITURA. It is categorised as a Write tool in the ArcGIS MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on group_add_users? +

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

What risk level is group_add_users? +

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

Can I rate-limit group_add_users? +

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

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

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