add_shared_mailbox_member · TrekMail MCP Server MCP

WHAT IT DOES

What add_shared_mailbox_member does on TrekMail MCP Server

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

WHY IT NEEDS A POLICY

Why add_shared_mailbox_member needs a policy

This tool creates or modifies mailbox membership and permissions, which are reversible data changes (members can be removed, permissions revoked). It does not delete data irreversibly, execute arbitrary code, or move money. The blast radius is medium because misconfiguration could grant unintended email access to sensitive communications, but the action is reversible.

From the tool's definition Tool name 'add_shared_mailbox_member' and description 'Add a member to a shared (team) mailbox' indicate creation/modification of mailbox membership.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_shared_mailbox_member Rate-limited

add_shared_mailbox_member 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": {
    "add_shared_mailbox_member": {
      "limits": [
        {
          "counter": "add_shared_mailbox_member_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 TrekMail MCP Server, so you can run agents against it safely.

FAQ

Questions about add_shared_mailbox_member

What does the add_shared_mailbox_member tool do? +

Add a member to a shared (team) mailbox. All members can read incoming mail. Optionally grant. It is categorised as a Write tool in the TrekMail MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on add_shared_mailbox_member? +

Register the TrekMail MCP Server MCP server in PolicyLayer and add a rule for add_shared_mailbox_member: 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 TrekMail MCP Server. Nothing to install.

What risk level is add_shared_mailbox_member? +

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

Can I rate-limit add_shared_mailbox_member? +

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

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

add_shared_mailbox_member is provided by the TrekMail MCP Server MCP server (trekmail/mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.