cart_add_discount_code

WHAT IT DOES

What cart_add_discount_code does on MCP Dynamics 365 Commerce Server

AI agents use cart_add_discount_code to create or update resources in MCP Dynamics 365 Commerce Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your MCP Dynamics 365 Commerce Server environment.

WHY IT NEEDS A POLICY

Why cart_add_discount_code needs a policy

This tool creates or modifies cart data (applying discounts) without permanently deleting data. It is reversible—discount codes can be removed. While it affects financial calculations (discount amounts), the tool itself does not transfer money or create binding financial obligations; it merely applies pricing adjustments within a cart context. Therefore, it is categorized as Write rather than Financial.

From the tool's definition Tool name 'cart_add_discount_code' and description 'Add discount code' indicate the tool modifies cart state by adding a discount code, which is a reversible write operation that affects order totals and pricing.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

cart_add_discount_code Rate-limited

cart_add_discount_code 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": {
    "cart_add_discount_code": {
      "limits": [
        {
          "counter": "cart_add_discount_code_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 MCP Dynamics 365 Commerce Server, so you can run agents against it safely.

FAQ

Questions about cart_add_discount_code

What does the cart_add_discount_code tool do? +

Add discount code. It is categorised as a Write tool in the MCP Dynamics 365 Commerce 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 cart_add_discount_code? +

Register the MCP Dynamics 365 Commerce Server MCP server in PolicyLayer and add a rule for cart_add_discount_code: 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 Dynamics 365 Commerce Server. Nothing to install.

What risk level is cart_add_discount_code? +

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

Can I rate-limit cart_add_discount_code? +

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

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

cart_add_discount_code is provided by the MCP Dynamics 365 Commerce Server MCP server (jiantmo/mcp-commerce). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.