AI agents use create_contact to create or update resources in macOS Contacts MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your macOS Contacts MCP environment.
This tool creates new contact entries, which is a reversible write operation. Severity is medium because creating unwanted contacts could clutter the address book and potentially be used for spam/phishing purposes, but the action itself is reversible (contacts can be deleted). It does not execute arbitrary code, delete data, or move money.
From the tool's definition Tool name 'create_contact' and description 'Create a new contact' indicate data creation in the contacts database.
Documented attack patterns abuse exactly the kind of access create_contact gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and macOS Contacts MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for create_contact:
{
"version": "1",
"default": "deny",
"tools": {
"create_contact": {
"limits": [
{
"counter": "create_contact_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}create_contact 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.
Free to start. No card required.
Create a new contact. It is categorised as a Write tool in the macOS Contacts MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the macOS Contacts MCP server in PolicyLayer and add a rule for create_contact: 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 macOS Contacts MCP. Nothing to install.
create_contact is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the create_contact 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.
Set action: deny in the PolicyLayer policy for create_contact. 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.
create_contact is provided by the macOS Contacts MCP server (jcontini/macos-contacts-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from macOS Contacts MCP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
5 macOS Contacts MCP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.