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

Annotations declare destructiveHint=true, so the write/mutation nature is already conveyed. The description adds useful context (24-hour GMT times, draft staging for unpublished events) but omits permission requirements, side effects on the calendar, and what happens with repeat fields. Modest added value over annotations.

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, front-loaded with the core action and free of filler. The trailing 'Elvanto: calendar/events/create' endpoint reference is minor padding but not disruptive.

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 19-parameter mutation tool with a fully documented schema and a destructiveHint annotation, the definition covers the essentials: action, time format, and draft staging. Given the rich schema, the description is adequate, though auth/permission expectations go unstated.

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%, so every parameter is already documented, including the enum-constrained repeat/status/all_day fields. The description only restates the GMT time convention and draft status, adding no syntax or semantics beyond the schema. Baseline 3 applies.

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?

States a specific verb and resource ('Create an event on a calendar') and adds scope ('optionally repeating'). An agent can distinguish it from the read-only sibling elvanto_list_calendar_events, though no sibling is named explicitly.

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?

Offers one concrete usage tip ('Use status "draft" to stage it unpublished'), which is genuine guidance, but says nothing about when to prefer this vs other creation tools, prerequisites, or the required organizer/calendar_id setup. Usage is implied rather than framed.

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