list_event_instances

SERVERMcp Google Calendar SOURCE@a1-x-tech/mcp-google-calendar

Low RISK CLASS

Category Read

Parameters 82 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/a1-x-tech-mcp-google-calendar/list-event-instances.md

WHAT IT DOES

What list_event_instances does on Mcp Google Calendar

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

Parameter	Type	Required	Description
`event_id`	string	Yes	The recurring series master id (from list_events without single_events).
`time_max`	string	—	Only instances starting before this RFC3339 moment.
`time_min`	string	—	Only instances ending at/after this RFC3339 moment.
`time_zone`	string	—	IANA zone the response times are rendered in.
`page_token`	string	—	nextPageToken from the previous page.
`calendar_id`	string	Yes	The calendar id from list_calendars, or "primary" for the authenticated user's main calendar.
`max_results`	integer	—	Max instances per page (1..2500).
`show_deleted`	boolean	—	Include cancelled instances (status=cancelled).

Parameters from the server's own tool schema.

RISK

Why list_event_instances is rated Low

Even though list_event_instances only reads data, uncontrolled read access leaks sensitive information and racks up API costs: an agent caught in a retry loop can make thousands of calls a minute without anyone noticing.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs list_event_instances safely

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

list_event_instances Allowed

list_event_instances 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": {
    "list_event_instances": {}
  }
}

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

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

FAQ

Questions about list_event_instances

What does the list_event_instances tool do? +

Expands one recurring event (the series master id) into its individual instances, each with its own id (like masterId_20260901T100000Z) and concrete start/end. Use an instance id with update_event to reschedule a single occurrence, or with delete_event to cancel just that one; exceptions already made to the series show their changed times here. show_deleted=true includes cancelled occurrences. Bound the window with time_min/time_max — an unbounded infinite series is paginated via page_token. It is categorised as a Read tool in the Mcp Google Calendar MCP Server, which means it retrieves data without modifying state.

What parameters does list_event_instances accept? +

list_event_instances accepts 8 parameters: event_id, time_max, time_min, time_zone, page_token, calendar_id, max_results, show_deleted. Required: event_id, calendar_id. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on list_event_instances? +

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

What risk level is list_event_instances? +

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

Can I rate-limit list_event_instances? +

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

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

list_event_instances is provided by the Mcp Google Calendar MCP server (@a1-x-tech/mcp-google-calendar). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on Mcp Google Calendar, and thousands of servers like it.

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All 19 Mcp Google Calendar tools →

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Guides

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