create_buyer

THE RISK

Medium Risk

Why create_buyer needs a policy

Creating a buyer record is a write operation that modifies the marketplace state but is reversible (the buyer can be deleted/deactivated). It does not delete data (not Destructive), does not move money directly (not Financial), and does not execute arbitrary code or external operations (not Execute).

From the tool's definition Tool name 'create_buyer' and description 'Create a buyer in the marketplace' — the verb 'create' indicates a reversible write operation that adds a new entity to the marketplace database.

Documented attack patterns abuse exactly the kind of access create_buyer gives an agent:

POLICY

How to control create_buyer

PolicyLayer is an MCP gateway — it sits between your AI agents and Mcp Afip, and nothing reaches the server without passing your rules. This is the rule we recommend for create_buyer:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "create_buyer": {
      "limits": [
        {
          "counter": "create_buyer_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

create_buyer 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.

Create a free account and register Mcp Afip — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

LIMIT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Mcp Afip tools

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All 1300 Mcp Afip tools →

Write tools on other servers

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Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Argument validation → Checking tool call arguments against schema and policy before they run.
Scoped token → Per-person credentials that grant a defined subset of servers and tools.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about create_buyer

What does the create_buyer tool do? +

Create a buyer in the marketplace. It is categorised as a Write tool in the Mcp Afip MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create_buyer? +

Register the Mcp Afip MCP server in PolicyLayer and add a rule for create_buyer: 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 Afip. Nothing to install.

What risk level is create_buyer? +

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

Can I rate-limit create_buyer? +

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

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

create_buyer is provided by the Mcp Afip MCP server (codespar/mcp-dev-latam). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Mcp Afip tool call.

Start from Mcp Afip, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →