delete_transaction · Finance App MCP: Risk & Policy

WHAT IT DOES

What delete_transaction does on Finance App

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

WHY IT NEEDS A POLICY

Why delete_transaction needs a policy

Despite being named 'delete', this tool works by creating a reversing/offsetting transaction — a standard double-entry accounting technique. Since the original transaction is preserved and a new reversing entry is created, the operation is reversible and falls under Write rather than Destructive. The financial data is not permanently removed.

From the tool's definition Delete a transaction by creating a reversing transaction. Original is not hard-deleted.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

delete_transaction Rate-limited

delete_transaction 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": {
    "delete_transaction": {
      "limits": [
        {
          "counter": "delete_transaction_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about delete_transaction

What does the delete_transaction tool do? +

Delete a transaction by creating a reversing transaction. Original is not hard-deleted. It is categorised as a Write tool in the Finance App MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on delete_transaction? +

Register the Finance App MCP server in PolicyLayer and add a rule for delete_transaction: 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 Finance App. Nothing to install.

What risk level is delete_transaction? +

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

Can I rate-limit delete_transaction? +

Yes. Add a rate_limit block to the delete_transaction 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_transaction completely? +

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

delete_transaction is provided by the Finance App MCP server (youssefaltai/finance-app). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.