query_free_busy

Queries the free/busy information for a list of calendars over a time period.

SERVERCalendar SOURCEdeciduus/calendar-mcp

Low RISK CLASS

Category Read

Parameters 00 required

Recommended Allowedsee the rule below

Registry record Grade D, identity unverified Pull the record →

This record as markdown: /tools/deciduus-calendar-mcp/query-free-busy.md

WHAT IT DOES

What query_free_busy does on Calendar

AI agents call query_free_busy to retrieve information from Calendar without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

RISK

Why query_free_busy is rated Low

This tool queries and retrieves free/busy status information from calendars—a passive data retrieval operation with no side effects, no data modification, no code execution, and no destructive capability. It fits the Read category definition: 'retrieves or queries data; no side effects (search, list, get, fetch)'.

From the tool's definition Tool name 'query_free_busy' and description 'Queries the free/busy information for a list of calendars over a time period' indicates a read-only operation that retrieves calendar availability data without modifying or executing any actions.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs query_free_busy safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Calendar, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For query_free_busy, this is the rule to start with:

query_free_busy Allowed

query_free_busy is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "query_free_busy": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Calendar, apply this rule, and every query_free_busy call is checked against it from then on.

FAQ

Questions about query_free_busy

What does the query_free_busy tool do? +

Queries the free/busy information for a list of calendars over a time period. It is categorised as a Read tool in the Calendar MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on query_free_busy? +

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

What risk level is query_free_busy? +

query_free_busy is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit query_free_busy? +

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

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

query_free_busy is provided by the Calendar MCP server (deciduus/calendar-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on Calendar, and thousands of servers like it.

This server

All 12 Calendar tools →

Across the catalogue

claude_query on Claude Bridge → The MCP Attack Database →

Guides

Roll out MCP under one policy →Data exfiltration →MCP token cost →