calendar_create_event

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

With no annotations at all, the description carries the full burden, and it does disclose meaningful behavior: end auto-defaults to start + 1 hour (next day for all-day), timezone_name only applies to offset-less datetimes, and it returns the new event's uid. It stops short of side effects — no mention of invitations/notifications, whether duplicates are created, or what happens when calendar_name is omitted.

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 the action, then dense format rules with concrete examples (2026-11-06, America/Sao_Paulo) and no filler sentences. Every clause conveys a rule an agent would otherwise get wrong.

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 an 8-parameter mutation with no annotations and no output schema, the description covers formats, defaulting, and the return value but leaves the calendar selection, alarm semantics, and side effects unexplained. An agent could call it, but could also silently create the event in the wrong calendar.

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 coverage is 0%, so the description must carry parameter meaning, and it does well for start, end, and timezone_name. But four of eight parameters — calendar_name, alarm_minutes_before, location, description — are never mentioned, leaving the target calendar and alarm units/defaults entirely unspecified.

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?

Opens with a specific verb and resource ('Create a calendar event'), which cleanly separates it from calendar_update_event and calendar_delete_event. It never explicitly routes to or away from those siblings, but the operation type alone is unambiguous.

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?

Usage is implied by the verb, and the format rules (ISO date vs datetime, IANA timezone) do tell the agent how to call it. However there is no guidance on when to prefer calendar_update_event versus a fresh create, nor any prerequisite such as which calendar is used by default or whether authentication/permissions are required.

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