create_api · Postman MCP: Risk & Policy

WHAT IT DOES

What create_api does on Postman

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

WHY IT NEEDS A POLICY

Why create_api needs a policy

This tool creates a new API resource, which is a reversible write operation. It adds metadata and configuration to the Postman system but does not execute code, delete data, or move money. The impact is limited to API definition creation within the Postman workspace.

From the tool's definition Tool name is 'create_api' with description 'Create a new API'. The verb 'create' indicates a write operation that adds new data to the Postman workspace.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_api Rate-limited

create_api 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": {
    "create_api": {
      "limits": [
        {
          "counter": "create_api_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Postman, so you can run agents against it safely.

FAQ

Questions about create_api

What does the create_api tool do? +

Create a new API. It is categorised as a Write tool in the Postman 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_api? +

Register the Postman MCP server in PolicyLayer and add a rule for create_api: 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 Postman. Nothing to install.

What risk level is create_api? +

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

Can I rate-limit create_api? +

Yes. Add a rate_limit block to the create_api 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_api completely? +

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

create_api is provided by the Postman MCP server (postmanv3/postman-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.