contact_create_list · M365 MCP: Risk & Policy

WHAT IT DOES

What contact_create_list does on M365

AI agents use contact_create_list to create or update resources in M365 — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your M365 environment.

WHY IT NEEDS A POLICY

Why contact_create_list needs a policy

This tool creates a new contact list, which is a reversible modification to the user's contacts data. It does not delete, execute code, or move money. While the description is empty (lowering confidence slightly), the name and server context clearly indicate a Write operation. Severity is medium because unintended contact list creation affects organizational data but remains recoverable.

From the tool's definition Tool name 'contact_create_list' indicates creation of a new contact list in Microsoft 365 Contacts service.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

contact_create_list Rate-limited

contact_create_list 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": {
    "contact_create_list": {
      "limits": [
        {
          "counter": "contact_create_list_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 M365, so you can run agents against it safely.

FAQ

Questions about contact_create_list

What does the contact_create_list tool do? +

contact_create_list. It is categorised as a Write tool in the M365 MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on contact_create_list? +

Register the M365 MCP server in PolicyLayer and add a rule for contact_create_list: 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 M365. Nothing to install.

What risk level is contact_create_list? +

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

Can I rate-limit contact_create_list? +

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

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

contact_create_list is provided by the M365 MCP server (robin-collins/m365-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.