resend_send_email · UnClick MCP: Risk & Policy

WHAT IT DOES

What resend_send_email does on UnClick

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

PARAMETERS

Parameter	Type	Required
`to`	string	Yes
`from`	string	Yes
`html`	string	—
`text`	string	—
`api_key`	string	—
`subject`	string	Yes

Parameters from the server's own tool schema.

WHY IT NEEDS A POLICY

Why resend_send_email needs a policy

Sending an email via Resend modifies state in an external email service and can be reversed (deleted or unsent in many systems). This is a write action with moderate blast radius: an AI agent could send unwanted emails, but the impact is limited to email delivery and user disruption rather than permanent data loss or financial harm.

From the tool's definition Tool name and description state 'Send an email' — a write operation that creates/modifies data (message content stored in email systems) reversibly.

Risk signalsHandles credentials or secrets (api_key) · Accepts raw HTML/template content (html)

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

resend_send_email Rate-limited

resend_send_email 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": {
    "resend_send_email": {
      "limits": [
        {
          "counter": "resend_send_email_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches UnClick, so you can run agents against it safely.

FAQ

Questions about resend_send_email

What does the resend_send_email tool do? +

Send an email using Resend. It is categorised as a Write tool in the UnClick MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

What parameters does resend_send_email accept? +

resend_send_email accepts 6 parameters: to, from, html, text, api_key, subject. Required: to, from, subject. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on resend_send_email? +

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

What risk level is resend_send_email? +

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

Can I rate-limit resend_send_email? +

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

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

resend_send_email is provided by the UnClick MCP server (@unclick/mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.