add_label_to_card · Mcp Trello MCP: Risk & Policy

WHAT IT DOES

What add_label_to_card does on Mcp Trello

AI agents use add_label_to_card to create or update resources in Mcp Trello — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Mcp Trello environment.

WHY IT NEEDS A POLICY

Why add_label_to_card needs a policy

Adding a label modifies card state by attaching a label. This is a Write operation since it creates/modifies data reversibly without deleting or executing arbitrary code. Severity is medium because misuse could clutter cards with incorrect labels, affecting team organization and productivity, but the change is easily reversible and has no financial impact.

From the tool's definition Tool description states 'Add a label to a card', which is a create/modify operation that adds metadata to an existing Trello card. This is a reversible change (labels can be removed).

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_label_to_card Rate-limited

add_label_to_card 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "add_label_to_card": {
      "limits": [
        {
          "counter": "add_label_to_card_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Mcp Trello, so you can run agents against it safely.

FAQ

Questions about add_label_to_card

What does the add_label_to_card tool do? +

Add a label to a card. It is categorised as a Write tool in the Mcp Trello MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on add_label_to_card? +

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

What risk level is add_label_to_card? +

add_label_to_card is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit add_label_to_card? +

Yes. Add a rate_limit block to the add_label_to_card 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 add_label_to_card completely? +

Set action: deny in the PolicyLayer policy for add_label_to_card. 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 add_label_to_card? +

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