google-workspace-mcp

calendar_update_event

Update existing Google Calendar events by modifying only the fields you specify, such as summary, start time, end time, location, or description.

Instructions

Update an existing calendar event. Only provided fields are changed.

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": {
      "event_id": "<event_id>"
    },
    "name": "calendar_update_event"
  }
}

Input Schema

Name	Required	Default
`end`	No
`start`	No
`summary`	No
`event_id`	Yes
`location`	No
`timezone`	No	America/Toronto
`calendar_id`	No	primary
`description`	No

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Aug 2, 2026

TDQS

B3.3/5.0

Behavior3/5

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

No annotations are provided, so the description must carry the behavioral disclosure burden. It discloses that only provided fields are changed (a partial-update semantic), which is useful. But it omits other behavioral aspects like permissions, error conditions, or how clearing a field is handled, and gives no context on defaults like timezone or calendar_id.

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?

Two short sentences. Front-loaded with the core action, followed by a precise behavioral qualifier. No filler words.

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 8 parameters, no annotations, and no parameter description coverage, this description is under-specified. It doesn't address time formats, default calendar behavior, or how to unset fields, though the presence of an output schema reduces the need to document return values.

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

Parameters1/5

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

Input schema has 8 parameters with 0% description coverage. The description doesn't name or explain any specific parameter; 'provided fields' is a generic reference that doesn't clarify formats, defaults, or relationships. For example, start/end format and timezone semantics are undocumented.

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

Purpose5/5

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

The description uses the specific verb 'Update' with the resource 'calendar event' and scopes it to 'existing' events, clearly distinguishing this from calendar_create_event and calendar_delete_event. The phrase 'Only provided fields are changed' further defines its partial-update purpose.

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

Usage Guidelines3/5

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

No explicit when/when-not or alternative tool names are given. However, the word 'existing' implies this is for modifying current events rather than creating new ones, and the partial-update note implies usage guidance. This is implied but not explicit.

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

Deploy Server