crm_create_contact_property · HubSpot MCP Server MCP

WHAT IT DOES

What crm_create_contact_property does on HubSpot MCP Server

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

WHY IT NEEDS A POLICY

Why crm_create_contact_property needs a policy

This tool creates new schema/metadata within the CRM (a contact property definition) rather than retrieving or executing arbitrary operations. While it modifies the system structure, property creation is reversible and does not permanently destroy data or commit financial actions. The blast radius is limited to CRM configuration changes that an AI agent could introduce, which constitutes a Write-category risk.

From the tool's definition Tool name 'crm_create_contact_property' and description 'Create a new contact property' indicate the tool creates new data in the HubSpot CRM system. This is a reversible write operation—properties can be modified or deleted later.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

crm_create_contact_property Rate-limited

crm_create_contact_property 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": {
    "crm_create_contact_property": {
      "limits": [
        {
          "counter": "crm_create_contact_property_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 HubSpot MCP Server, so you can run agents against it safely.

FAQ

Questions about crm_create_contact_property

What does the crm_create_contact_property tool do? +

Create a new contact property. It is categorised as a Write tool in the HubSpot MCP 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 crm_create_contact_property? +

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

What risk level is crm_create_contact_property? +

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

Can I rate-limit crm_create_contact_property? +

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

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

crm_create_contact_property is provided by the HubSpot MCP Server MCP server (kozo93/hubspot-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.