set_contact_policy · MCP Agent Mail MCP: Risk & Policy

WHAT IT DOES

What set_contact_policy does on MCP Agent Mail

AI agents use set_contact_policy 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 set_contact_policy needs a policy

The tool likely creates or modifies contact policy data, making it a Write operation. Severity is medium because policy changes in a multi-agent coordination system could have broader effects on system behavior and inter-agent communication, but lacks the irreversibility of destructive operations. Confidence is moderate (0.65) due to the empty description and inference from the tool name and server context alone.

From the tool's definition Tool name 'set_contact_policy' indicates it modifies a policy setting. The description is empty, limiting direct evidence.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_contact_policy Rate-limited

set_contact_policy 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": {
    "set_contact_policy": {
      "limits": [
        {
          "counter": "set_contact_policy_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 set_contact_policy

What does the set_contact_policy tool do? +

set_contact_policy. 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 set_contact_policy? +

Register the MCP Agent Mail MCP server in PolicyLayer and add a rule for set_contact_policy: 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 set_contact_policy? +

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

Can I rate-limit set_contact_policy? +

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

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

set_contact_policy 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.