update_subscription · Rebillia MCP Server MCP: Risk & Policy

WHAT IT DOES

What update_subscription does on Rebillia MCP Server

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

WHY IT NEEDS A POLICY

Why update_subscription needs a policy

This tool modifies an existing subscription record via PUT, which is a reversible write operation. However, it carries high severity because changes to payment methods, gateways, currencies, or billing dates on a subscription can have significant financial downstream effects (wrong charges, billing disruptions) if misused by an AI agent.

From the tool's definition Update a subscription. PUT /subscriptions/{subscriptionId}. Optional: name, companyCurrencyId, companyGatewayId, customerPaymentMethodId, detail, effectiveStartDate, billingAddressId, shippingAddressId.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_subscription Rate-limited

update_subscription 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": {
    "update_subscription": {
      "limits": [
        {
          "counter": "update_subscription_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 Rebillia MCP Server, so you can run agents against it safely.

FAQ

Questions about update_subscription

What does the update_subscription tool do? +

Update a subscription. PUT /subscriptions/{subscriptionId}. Optional: name, companyCurrencyId, companyGatewayId, customerPaymentMethodId, detail, effectiveStartDate, billingAddressId, shippingAddressId. It is categorised as a Write tool in the Rebillia MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on update_subscription? +

Register the Rebillia MCP Server MCP server in PolicyLayer and add a rule for update_subscription: 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 Rebillia MCP Server. Nothing to install.

What risk level is update_subscription? +

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

Can I rate-limit update_subscription? +

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

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

update_subscription is provided by the Rebillia MCP Server MCP server (rhinosaas/rebillia-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.