google-workspace-alias-mcp

update_event

Modify an existing calendar event's title, time, location, description, or attendees using Google Calendar.

Instructions

Update an existing calendar event

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": {
      "eventId": "<eventId>"
    },
    "name": "update_event"
  }
}

Input Schema

Name	Required	Description	Default
`end`	No	End time (ISO format)
`start`	No	Start time (ISO format)
`eventId`	Yes	Event ID to update
`summary`	No	Event title
`location`	No	Event location
`attendees`	No	List of attendee emails
`calendarId`	No	Calendar ID	primary
`description`	No	Event description

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.1.0Jul 10, 2026

TDQS

C2.9/5.0

Behavior2/5

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

No annotations provided, so description carries full burden. It only says 'update an existing calendar event' without disclosing side effects, permissions needed, or behavior when eventId is invalid. The description adds minimal value beyond the tool name.

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

Conciseness4/5

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

Single sentence, no waste. However, it could be slightly expanded to include key constraints like required eventId.

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 an update tool with 8 parameters and no output schema, the description is insufficient. It doesn't explain return values, error handling, or partial update semantics. Ideal would include that only provided fields are updated (patch behavior).

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?

Schema covers 100% of parameters with descriptions, so description need not repeat. Baseline 3 is appropriate as it adds no additional meaning to the parameters.

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 tool updates an event, which differentiates it from create and delete siblings. However, it doesn't explicitly distinguish from more specific sibling tools like batch_modify_emails, which is acceptable given the different resource.

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?

No guidance on when to use this vs alternatives like create_event or delete_event. No mention of prerequisites or context for using the eventId required parameter.

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