Returns every account known to mailbox: id, email, provider (gmail/qq/163/outlook/...), IMAP/SMTP host. Use the returned
AI agents call account_list to retrieve information from MCP Email Service without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool queries and lists account metadata (id, email, provider, IMAP/SMTP hosts) without modifying, deleting, or executing operations. It is a straightforward read operation. Severity is low because exposing account metadata has limited immediate blast radius; the actual risk materializes when combined with other tools like email_delete or email_move that can act on these accounts.
From the tool's definition Tool name is 'account_list' and description states it 'Returns every account known to mailbox' — a pure retrieval operation with no side effects.
Risk signalsBulk/mass operation — affects multiple targets
Documented attack patterns abuse exactly the kind of access account_list gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and MCP Email Service, and nothing reaches the server without passing your rules. This is the rule we recommend for account_list:
{
"version": "1",
"default": "deny",
"tools": {
"account_list": {}
}
}account_list 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.
Returns every account known to mailbox: id, email, provider (gmail/qq/163/outlook/...), IMAP/SMTP host. Use the returned. It is categorised as a Read tool in the MCP Email Service MCP Server, which means it retrieves data without modifying state.
Register the MCP Email Service MCP server in PolicyLayer and add a rule for account_list: 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 MCP Email Service. Nothing to install.
account_list 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 account_list 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 account_list. 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.
account_list is provided by the MCP Email Service MCP server (leeguooooo/mailbox). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from MCP Email Service, 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.
16 MCP Email Service tools catalogued and risk-classified — across an index of 43,000+ MCP servers.