delete_attachment

THE RISK

Critical Risk

Why delete_attachment needs a policy

This tool irreversibly removes attachments from Trello cards. While the blast radius is limited to a single attachment on a card (not a full board or database), the action cannot be undone without restoring from backups. Destructive operations that permanently remove data take precedence over Write or Execute categories.

From the tool's definition Tool name 'delete_attachment' combined with description 'Delete an attachment from a card' explicitly indicates irreversible deletion of data. The verb 'Delete' and 'remove' confirm destructive intent.

Documented attack patterns abuse exactly the kind of access delete_attachment gives an agent:

POLICY

How to control delete_attachment

PolicyLayer is an MCP gateway — it sits between your AI agents and Trello, and nothing reaches the server without passing your rules. This is the rule we recommend for delete_attachment:

policy.json

{
  "version": "1",
  "default": "deny",
  "hide": [
    "delete_attachment"
  ]
}

delete_attachment disappears from the agent's tool list entirely, and any attempt to call it is denied. The rest of the server keeps working.

Create a free account and register Trello — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

RESTRICT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Trello tools

Destructive delete_board Permanently delete a board. Use this tool with caution as deletion cannot be undone. Destructive delete_card Permanently delete a card. Use this tool with caution as deletion cannot be undone. Destructive delete_checkitem Delete a checkitem from a checklist. Use this tool to remove an item from a checklist. Destructive delete_checklist Delete a checklist. Use this tool to remove a checklist from a card. Destructive delete_label Permanently delete a label. Use this tool with caution as deletion cannot be undone. Destructive close_board Close (archive) a board. Use this tool to archive a board without deleting it. Write remove_label Remove a label from a card. Use this tool to update the categorization of a card. Write remove_label_from_card Remove a label from a card. Use this tool to update the categorization of a card.

All 76 Trello tools →

Destructive tools on other servers

Android Forensics ADB MCP Server create_full_backup 0xarchive web3_revoke_key Frida Game Hacking MCP clear_scan cPanel MCP Server clear_spam_box

Go deeper

Critical-risk tools in Trello → Every critical-risk tool this server exposes, in one view.
All critical-risk MCP tools → Every critical-risk tool across the catalogue, and the policy pattern that contains them.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Blast radius → How much damage one compromised or confused agent can do — and how to bound it.
Tool call approval → Approval gates on individual tool calls: auto-allow, prompt, or deny.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about delete_attachment

What does the delete_attachment tool do? +

Delete an attachment from a card. Use this tool to remove a file or link from a card. It is categorised as a Destructive tool in the Trello MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.

How do I enforce a policy on delete_attachment? +

Register the Trello MCP server in PolicyLayer and add a rule for delete_attachment: 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 Trello. Nothing to install.

What risk level is delete_attachment? +

delete_attachment is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.

Can I rate-limit delete_attachment? +

Yes. Add a rate_limit block to the delete_attachment 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.

How do I block delete_attachment completely? +

Set action: deny in the PolicyLayer policy for delete_attachment. 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.

What MCP server provides delete_attachment? +

delete_attachment is provided by the Trello MCP server (v4lheru/trello-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Trello tool call.

Start from Trello, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →