create_booking · Cal Com MCP Server for Customers MCP

WHAT IT DOES

What create_booking does on Cal Com MCP Server for Customers

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

WHY IT NEEDS A POLICY

Why create_booking needs a policy

This tool creates calendar bookings, which are new data records in Cal.com. This is reversible (bookings can be cancelled or modified), so it falls under Write rather than Destructive. Severity is high because a compromised AI agent could spam bookings, create fraudulent appointments on behalf of the user, or cause calendar chaos affecting both the user and invitees.

From the tool's definition Tool name 'create_booking' combined with server description stating it 'enables AI assistants to book meetings' and 'manage Cal.com scheduling'. The tool description is empty, but the sibling context and tool name clearly indicate data creation.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_booking Rate-limited

create_booking 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_booking": {
      "limits": [
        {
          "counter": "create_booking_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 Cal Com MCP Server for Customers, so you can run agents against it safely.

FAQ

Questions about create_booking

What does the create_booking tool do? +

create_booking. It is categorised as a Write tool in the Cal Com MCP Server for Customers 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_booking? +

Register the Cal Com MCP Server for Customers MCP server in PolicyLayer and add a rule for create_booking: 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 Cal Com MCP Server for Customers. Nothing to install.

What risk level is create_booking? +

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

Can I rate-limit create_booking? +

Yes. Add a rate_limit block to the create_booking 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_booking completely? +

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

create_booking is provided by the Cal Com MCP Server for Customers MCP server (niopub/calcom-mcp-for-customers). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.