Download attachments from an email. Returns base64-encoded content.
AI agents call mail__get_attachments to retrieve information from Proton-MCP without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves and returns email attachments in base64-encoded format. It performs data retrieval with no side effects—it neither creates, modifies, deletes, executes code, nor moves money. The attachment content is returned to the caller but the original data remains unchanged. This is a classic Read operation.
From the tool's definition Tool name contains 'get_attachments' and description states 'Download attachments from an email. Returns base64-encoded content.' The verb 'download' in this context means retrieval of existing data without modification or deletion.
Documented attack patterns abuse exactly the kind of access mail__get_attachments gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Proton-MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for mail__get_attachments:
{
"version": "1",
"default": "deny",
"tools": {
"mail__get_attachments": {}
}
}mail__get_attachments is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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Download attachments from an email. Returns base64-encoded content. It is categorised as a Read tool in the Proton-MCP MCP Server, which means it retrieves data without modifying state.
Register the Proton- MCP server in PolicyLayer and add a rule for mail__get_attachments: 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 Proton-MCP. Nothing to install.
mail__get_attachments 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 mail__get_attachments 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 mail__get_attachments. 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.
mail__get_attachments is provided by the Proton- MCP server (jorgenclaw/proton-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Proton-MCP, 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.
36 Proton-MCP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.