download_attachment

What download_attachment does on Trello

AI agents call download_attachment to retrieve information from Trello without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

Why download_attachment is rated Low

This tool retrieves and returns data (an attachment in base64 format) without creating, modifying, deleting, or executing operations. It is a pure read operation that queries and fetches an existing file attachment from a Trello card. The base64 encoding is a data transformation for transport, not a side effect. There is no destructive impact, financial transaction, or code execution involved.

From the tool's definition Tool name 'download_attachment' and description 'Download an attachment from a card. Returns base64-encoded data that can be saved or viewed.' indicate retrieval of existing data with no modification or deletion of content.

The rule that runs download_attachment safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Trello, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For download_attachment, this is the rule to start with:

{
  "version": "1",
  "default": "deny",
  "tools": {
    "download_attachment": {}
  }
}

Questions about download_attachment