AI agents call list_emails to retrieve information from Google Toolbox without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves/queries email data from a Gmail inbox without side effects. It performs a simple listing operation, which is characteristic of Read category tools. The low severity reflects minimal blast radius—an AI agent misusing this tool would only have access to read inbox contents, not modify or delete them.
From the tool's definition Tool name 'list_emails' and description 'List recent emails from Gmail inbox' indicate data retrieval with no modification or deletion.
Documented attack patterns abuse exactly the kind of access list_emails gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Google Toolbox, and nothing reaches the server without passing your rules. This is the rule we recommend for list_emails:
{
"version": "1",
"default": "deny",
"tools": {
"list_emails": {}
}
}list_emails is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
List recent emails from Gmail inbox. It is categorised as a Read tool in the Google Toolbox MCP Server, which means it retrieves data without modifying state.
Register the Google Toolbox MCP server in PolicyLayer and add a rule for list_emails: 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 Google Toolbox. Nothing to install.
list_emails is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the list_emails 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 list_emails. 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.
list_emails is provided by the Google Toolbox MCP server (jikime/py-mcp-google-toolbox). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Google Toolbox, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
11 Google Toolbox tools catalogued and risk-classified — across an index of 43,000+ MCP servers.