Google Calendar MCP Server

create_event

Create Google Calendar events with titles, times, descriptions, locations, attendees, and reminders using structured input parameters.

Instructions

Create a calendar event with specified details

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "summary": "<summary>",
      "start_time": "<start_time>",
      "end_time": "<end_time>"
    },
    "name": "create_event"
  }
}

Input Schema

Name	Required	Description
`summary`	Yes	Event title
`start_time`	Yes	Start time (ISO format)
`end_time`	Yes	End time (ISO format)
`description`	No	Event description
`location`	No	Event location
`attendees`	No	List of attendee emails
`reminders`	No	Reminder settings for the event

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.2.1Jan 24, 2026

TDQS

C2.9/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. While 'create' implies a write/mutation operation, the description doesn't disclose important behavioral aspects like required permissions, whether the event is immediately published, what happens with duplicate events, error conditions, or what the response contains. For a mutation tool with zero annotation coverage, this represents a significant gap in behavioral transparency.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that gets straight to the point without any wasted words. It's appropriately sized for the tool's complexity and front-loads the essential information. Every word earns its place in this concise formulation.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutation tool with 7 parameters (including complex nested objects) and no annotations or output schema, the description is inadequate. It doesn't explain what happens after creation, error handling, authentication requirements, or the scope of the operation (personal vs shared calendar). The 100% schema coverage helps with parameters, but the overall context for using this tool remains incomplete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description mentions 'specified details' which implies parameters exist, but doesn't elaborate on what those details are. With 100% schema description coverage, the schema already documents all 7 parameters thoroughly. The description adds no meaningful parameter semantics beyond what's already in the schema, so it meets the baseline of 3 when schema coverage is complete.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('create') and resource ('calendar event'), making the purpose immediately understandable. However, it lacks differentiation from sibling tools, but since there are no sibling tools on this server, this limitation is less critical. The phrase 'with specified details' adds some specificity about what can be configured.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives, prerequisites, or constraints. It simply states what the tool does without any context about appropriate usage scenarios, timing considerations, or limitations. With no sibling tools, the need for differentiation is reduced, but still lacks basic usage context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server

Other Tools

create_eventC