create_recurring_event

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

Annotations are minimal (readOnlyHint=false, etc.), so the description carries the burden. It discloses that the tool creates a recurring event, supports markdown in description, and returns the event ID. It does not mention side effects, authentication needs, or rate limits, but for a creation tool, this level of detail is adequate.

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?

The description is three sentences, each serving a distinct purpose: stating the core function, adding parameter behavior, and mentioning the return. It is front-loaded with the most important information and contains no superfluous words.

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?

With a rich schema (100% coverage) and an output schema (indicated by context), the description does not need to re-document parameters. It covers the essential behavioral aspects (calendarId default, return value) and mentions RFC5545, which is helpful for understanding the recurrence format. It is complete enough for the tool's intended use.

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 100%, so the schema documents all 16 parameters. The description adds context for calendarId (targets specific calendar vs primary personal) and states the return value (created event ID), which are not in the schema. This added value justifies a score above baseline 3.

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?

The description clearly states the action ('Create') and the resource ('recurring calendar event'). It mentions RFC5545 RRULE rules, distinguishing it from non-recurring event tools like create_event. The verb and resource are specific and 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?

The description provides clear guidance on the optional calendarId parameter, explaining default behavior when omitted. It does not explicitly state when to use this tool versus create_event, but the differentiation is evident from the name and description. No explicit exclusions or alternatives are mentioned, which is acceptable for a straightforward creation tool.

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