Create Calendar Event

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

Beyond the annotations (which only say readOnlyHint=false, idempotentHint=false, destructiveHint=false), the description adds genuinely useful behavior: no invitations or email reminders are sent, the credential needs calendar.write, and the UID must be retained for reconciliation after an uncertain result. It does not explain how a duplicate UID is treated (conflict vs. overwrite), which is the remaining gap for a non-idempotent write.

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?

Three short sentences with the capability, permission requirement, and retry rule front-loaded; nothing is filler. The second clause is telegraphic ("Retain the required UID before dispatch") but still parseable.

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?

Nine parameters with full schema coverage and an output schema means return values need no explanation; the description covers the two things structure cannot: notification side effects and safe retry after an ambiguous failure. Only the duplicate-UID/conflict outcome is left unstated for a 6-required-param write tool.

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 100% and the UID reconciliation/never-repeat guidance is already written verbatim into the uid and Idempotency-Key parameter descriptions. The description therefore restates rather than adds meaning; baseline 3 is appropriate.

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?

"Save an event without invitations or email reminders" states a specific verb (save/create) and resource (calendar event) plus an important scope qualifier: no attendee invitations or mail notifications. It does not explicitly name the sibling create/update calendar-event tools or say how it differs from them, so it stops short of a 5.

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 qualifier (use this when you want an event with no invitations/reminders) and a prerequisite is disclosed ("Requires calendar.write"). There is no explicit when-not guidance or named alternative such as mailbox_update_calendar_event or the qubrics_ variant, which matters given several near-identical calendar siblings.

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