Move emails to a different mailbox. Requires a mailbox ID — use get_mailboxes first to find the target mailbox ID by name.
AI agents use move_emails to create or update resources in JMAP MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your JMAP MCP environment.
Moving emails changes their mailbox location, which is a reversible Write operation. While it modifies email metadata (mailbox association), it does not delete data (thus not Destructive) or execute arbitrary code (thus not Execute). The medium severity reflects that bulk email movement could disrupt workflows or organizational structures, but the operation remains reversible.
From the tool's definition Tool description states "Move emails to a different mailbox" — a reversible modification of email state/location. The verb 'move' indicates data is being modified but not destroyed, and the operation is undoable (emails can be moved back).
Documented attack patterns abuse exactly the kind of access move_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 move_emails:
{
"version": "1",
"default": "deny",
"tools": {
"move_emails": {
"limits": [
{
"counter": "move_emails_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}move_emails 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.
Move emails to a different mailbox. Requires a mailbox ID — use get_mailboxes first to find the target mailbox ID by name. It is categorised as a Write tool in the JMAP MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the JMAP MCP server in PolicyLayer and add a rule for move_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.
move_emails 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 move_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 move_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.
move_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.