assign_to_group · Whiteboard MCP: Risk & Policy

WHAT IT DOES

What assign_to_group does on Whiteboard

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

WHY IT NEEDS A POLICY

Why assign_to_group needs a policy

This tool creates or modifies data (element grouping) within an Excalidraw diagram without deleting or executing code. The modification is reversible (groups can be ungrouped or reassigned), making it a Write operation rather than Execute or Destructive. Severity is medium because misuse could corrupt diagram organization, but the effect is localized to a single canvas and easily undone.

From the tool's definition Tool description states 'Add elements to a logical group by appending a groupId to their' — modifies element metadata by appending groupId, which changes diagram structure reversibly.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

assign_to_group Rate-limited

assign_to_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": {
    "assign_to_group": {
      "limits": [
        {
          "counter": "assign_to_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 Whiteboard, so you can run agents against it safely.

FAQ

Questions about assign_to_group

What does the assign_to_group tool do? +

Add elements to a logical group by appending a groupId to their. It is categorised as a Write tool in the Whiteboard MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on assign_to_group? +

Register the Whiteboard MCP server in PolicyLayer and add a rule for assign_to_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 Whiteboard. Nothing to install.

What risk level is assign_to_group? +

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

Can I rate-limit assign_to_group? +

Yes. Add a rate_limit block to the assign_to_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 assign_to_group completely? +

Set action: deny in the PolicyLayer policy for assign_to_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 assign_to_group? +

assign_to_group is provided by the Whiteboard MCP server (kamiazya/whiteboard). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.