vtex_update_item_quantity · MCP VTEX Server MCP

WHAT IT DOES

What vtex_update_item_quantity does on MCP VTEX Server

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

WHY IT NEEDS A POLICY

Why vtex_update_item_quantity needs a policy

This tool modifies cart contents by changing item quantities, which is a Write operation. It creates or modifies data reversibly without permanently deleting data (Destructive) or moving money (Financial). While it operates in an e-commerce context, the severity is medium rather than high because the impact is limited to a single user's cart state, and the action is easily undone by adjusting quantities again.

From the tool's definition Tool name 'vtex_update_item_quantity' and description 'Update item quantity in cart' indicate modification of cart data. The action is reversible—quantities can be adjusted up or down, and items remain in the system.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

vtex_update_item_quantity Rate-limited

vtex_update_item_quantity 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": {
    "vtex_update_item_quantity": {
      "limits": [
        {
          "counter": "vtex_update_item_quantity_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 VTEX Server, so you can run agents against it safely.

FAQ

Questions about vtex_update_item_quantity

What does the vtex_update_item_quantity tool do? +

Update item quantity in cart. It is categorised as a Write tool in the MCP VTEX 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 vtex_update_item_quantity? +

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

What risk level is vtex_update_item_quantity? +

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

Can I rate-limit vtex_update_item_quantity? +

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

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

vtex_update_item_quantity is provided by the MCP VTEX Server MCP server (leosepulveda/mcp-vtex). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.