Remove a contact from a segment in Resend (by contact ID or email). Before using this tool, you MUST double-check with the user that they want to remove the contact from the segment.
AI agents use remove-contact-from-segment to create or update resources in Email Sending MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Email Sending MCP environment.
Removing a contact from a segment modifies the contact's segment membership, which is a reversible write operation. The contact itself is not deleted, just disassociated from the segment. The instruction to double-check with the user suggests potential impact, but the action can be undone by re-adding the contact. Severity is medium as misuse could disrupt email marketing campaigns targeting that segment.
From the tool's definition Remove a contact from a segment in Resend (by contact ID or email)
Documented attack patterns abuse exactly the kind of access remove-contact-from-segment gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Email Sending MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for remove-contact-from-segment:
{
"version": "1",
"default": "deny",
"tools": {
"remove-contact-from-segment": {
"limits": [
{
"counter": "remove-contact-from-segment_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}remove-contact-from-segment 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.
Free to start. No card required.
Remove a contact from a segment in Resend (by contact ID or email). Before using this tool, you MUST double-check with the user that they want to remove the contact from the segment. It is categorised as a Write tool in the Email Sending MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Email Sending MCP server in PolicyLayer and add a rule for remove-contact-from-segment: 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 Email Sending MCP. Nothing to install.
remove-contact-from-segment is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the remove-contact-from-segment 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.
Set action: deny in the PolicyLayer policy for remove-contact-from-segment. 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.
remove-contact-from-segment is provided by the Email Sending MCP server (resend/resend-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 77 Email Sending MCP tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
77 Email Sending MCP tools catalogued and risk-classified — across an index of 42,500+ MCP servers.