Create an event

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

Beyond annotations, it discloses timezone interpretation ('Without an offset it is read in the calendar's own timezone'), side-effect emailing ('They receive an invitation email unless send_notifications is false'), and account selection. No contradiction with readOnlyHint=false or destructiveHint=false.

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

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

Front-loaded with core purpose and sibling routing, followed by a tidy Args block where every line adds non-obvious detail. No filler or repetition of schema-only information.

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

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

For a 9-parameter creation tool with no schema descriptions, it covers all parameters, timezone semantics, notification side effects, and account resolution; an output schema exists to describe return values. The description is fully capable of guiding correct invocation.

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

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

Schema description coverage is 0%, so the description carries the full burden and succeeds: every one of the 9 parameters is explained with real meaning, a required marker on summary, ISO format guidance, and defaults for send_notifications/account. It adds value the bare schema cannot.

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

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

Description opens with 'Create an event with explicit start and end times, and optional attendees' — a specific verb, resource, and key behavior. It also names quick_add_event as the alternative for natural-language one-liners, so an agent can distinguish the two creation paths.

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

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

Explicitly states when to prefer quick_add_event ('For a one-line natural-language description... prefer quick_add_event') and implies this tool is for structured, explicit-time creation. This is direct routing guidance rather than leaving the choice to inference.

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