respond_contact · MCP Agent Mail MCP: Risk & Policy

WHAT IT DOES

What respond_contact does on MCP Agent Mail

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

WHY IT NEEDS A POLICY

Why respond_contact needs a policy

The tool name suggests sending a response to a contact, which is a Write operation (creating a new message or reply). However, the description is empty, which significantly lowers confidence. Based on the server's purpose as a messaging/coordination layer and sibling tools like 'fetch_inbox' and 'acknowledge_message', this tool likely creates or sends a message response, placing it in the Write category.

From the tool's definition Tool name 'respond_contact' and server context involving message threading and agent coordination.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

respond_contact Rate-limited

respond_contact 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": {
    "respond_contact": {
      "limits": [
        {
          "counter": "respond_contact_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 MCP Agent Mail, so you can run agents against it safely.

FAQ

Questions about respond_contact

What does the respond_contact tool do? +

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

How do I enforce a policy on respond_contact? +

Register the MCP Agent Mail MCP server in PolicyLayer and add a rule for respond_contact: 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 MCP Agent Mail. Nothing to install.

What risk level is respond_contact? +

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

Can I rate-limit respond_contact? +

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

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

respond_contact is provided by the MCP Agent Mail MCP server (omelchmichael/mcp_agent_mail). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.