vtex_authenticate_user · MCP VTEX Server MCP: Risk & Policy

WHAT IT DOES

What vtex_authenticate_user does on MCP VTEX Server

AI agents invoke vtex_authenticate_user to trigger actions in MCP VTEX Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why vtex_authenticate_user needs a policy

Authentication operations execute an external process (credential verification/session creation) that produces side effects such as session tokens, audit logs, and access grants. This is not a simple read since it creates a session state. Severity is high because misuse could grant unauthorized access to the VTEX platform, which manages payments, orders, and customer data.

From the tool's definition Authenticate user with credentials

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

vtex_authenticate_user Rate-limited

vtex_authenticate_user stays usable, but rate-capped — a runaway agent can't fire it dozens of times 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_authenticate_user": {
      "limits": [
        {
          "counter": "vtex_authenticate_user_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-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_authenticate_user

What does the vtex_authenticate_user tool do? +

Authenticate user with credentials. It is categorised as a Execute tool in the MCP VTEX Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on vtex_authenticate_user? +

Register the MCP VTEX Server MCP server in PolicyLayer and add a rule for vtex_authenticate_user: 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_authenticate_user? +

vtex_authenticate_user is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit vtex_authenticate_user? +

Yes. Add a rate_limit block to the vtex_authenticate_user 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_authenticate_user completely? +

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

vtex_authenticate_user 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.