AI agents call get_emails to retrieve information from JMAP MCP without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves email messages by identifier, which is a read-only query operation. No data is created, modified, deleted, or executed. The action has no side effects beyond fetching requested information. This is consistent with the Read category for tools that retrieve or query data without side effects.
From the tool's definition Tool name 'get_emails' and description 'Get specific emails by their IDs' indicates retrieval of existing data with no modification or side effects.
Documented attack patterns abuse exactly the kind of access get_emails gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and JMAP MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for get_emails:
{
"version": "1",
"default": "deny",
"tools": {
"get_emails": {}
}
}get_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.
Get specific emails by their IDs. Use the. It is categorised as a Read tool in the JMAP MCP MCP Server, which means it retrieves data without modifying state.
Register the JMAP MCP server in PolicyLayer and add a rule for get_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 JMAP MCP. Nothing to install.
get_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 get_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 get_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.
get_emails is provided by the JMAP MCP server (wyattjoh/jmap-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 11 JMAP MCP tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
11 JMAP MCP tools catalogued and risk-classified — across an index of 42,500+ MCP servers.