compose_email_reply · AIOS Co-Founder MCP: Risk & Policy

WHAT IT DOES

What compose_email_reply does on AIOS Co-Founder MCP

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

WHY IT NEEDS A POLICY

Why compose_email_reply needs a policy

The tool creates/writes a draft email, which is a reversible write operation. Since it explicitly never sends the email, there is no risk of unintended communication. The blast radius is low as drafts can be reviewed and discarded.

From the tool's definition "Generate an email reply draft (never sends)" — creates a draft but explicitly does not send

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

compose_email_reply Rate-limited

compose_email_reply 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": {
    "compose_email_reply": {
      "limits": [
        {
          "counter": "compose_email_reply_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 AIOS Co-Founder MCP, so you can run agents against it safely.

FAQ

Questions about compose_email_reply

What does the compose_email_reply tool do? +

Generate an email reply draft (never sends). It is categorised as a Write tool in the AIOS Co-Founder MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on compose_email_reply? +

Register the AIOS Co-Founder MCP server in PolicyLayer and add a rule for compose_email_reply: 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 AIOS Co-Founder MCP. Nothing to install.

What risk level is compose_email_reply? +

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

Can I rate-limit compose_email_reply? +

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

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

compose_email_reply is provided by the AIOS Co-Founder MCP server (varun-b-nagaraj/python-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.