AI agents call delete_message to permanently remove resources in Gmail MCP — typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
This tool irreversibly removes email data from Gmail. Once executed, the message cannot be recovered through normal means. The permanent and immediate nature of the deletion, combined with no undo capability, places this in the Destructive category. Severity is high because an AI agent misconfigured or adversarially prompted could delete critical emails, business records, or evidence.
From the tool's definition Tool name is 'delete_message' with description 'Immediately and permanently delete a message' — uses keywords 'permanently delete' indicating irreversible data destruction.
Documented attack patterns abuse exactly the kind of access delete_message gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Gmail MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for delete_message:
{
"version": "1",
"default": "deny",
"hide": [
"delete_message"
]
}delete_message disappears from the agent's tool list entirely, and any attempt to call it is denied. The rest of the server keeps working.
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Immediately and permanently delete a message. It is categorised as a Destructive tool in the Gmail MCP MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the Gmail MCP server in PolicyLayer and add a rule for delete_message: 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 Gmail MCP. Nothing to install.
delete_message is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the delete_message 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 delete_message. 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.
delete_message is provided by the Gmail MCP server (shinzo-labs/gmail-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 65 Gmail MCP tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
65 Gmail MCP tools catalogued and risk-classified — across an index of 42,500+ MCP servers.