rental_add_tenant · Excel Finance MCP: Risk & Policy

WHAT IT DOES

What rental_add_tenant does on Excel Finance MCP

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

WHY IT NEEDS A POLICY

Why rental_add_tenant needs a policy

This tool creates a new tenant record in a rental property management system, which is a reversible data modification (Write category). Severity is medium because misuse could create fraudulent or unauthorized tenant entries, affecting property management operations and potentially financial obligations, but the effect is limited to record creation without immediate financial impact or data destruction.

From the tool's definition Tool name 'rental_add_tenant' and description 'Add a new tenant to the system' indicate data creation/modification. The server context involves 'rental property management', confirming this is a Write operation that creates a new tenant record.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

rental_add_tenant Rate-limited

rental_add_tenant 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": {
    "rental_add_tenant": {
      "limits": [
        {
          "counter": "rental_add_tenant_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 Excel Finance MCP, so you can run agents against it safely.

FAQ

Questions about rental_add_tenant

What does the rental_add_tenant tool do? +

Add a new tenant to the system. It is categorised as a Write tool in the Excel Finance MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on rental_add_tenant? +

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

What risk level is rental_add_tenant? +

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

Can I rate-limit rental_add_tenant? +

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

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

rental_add_tenant is provided by the Excel Finance MCP server (jeremycharlesgillespie/excel-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.