calendar_recurring_instances

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

With no annotations provided, the description must disclose behavioral traits. It states 'List instances' implying a read-only operation, but does not mention whether results are paginated, if it returns all instances or only a subset, what happens if the event is not recurring, or authentication/permission requirements. Minimal transparency.

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?

A single, front-loaded sentence that conveys the core action and target. It is concise and to the point, but could be slightly expanded to include key context like the fact that it lists occurrences. Still, no wasted 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?

Given the lack of output schema and annotations, the description is too sparse. It does not explain what an 'instance' is, how the result differs from a regular event list, or provide any usage context. For a tool with 3 parameters and no structured metadata, the description should offer more complete guidance.

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?

The input schema has 100% coverage with descriptions for each parameter, but the tool description adds no additional meaning. It does not explain that 'eventId' must be a recurring event's ID, or what 'maxResults' defaults to, or how 'calendarId' is used. The description fails to enrich the parameter semantics beyond the schema.

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 verb 'List' and the resource 'instances of a recurring Google Calendar event'. It distinguishes from sibling tools like calendar_list_events by specifying recurring event instances, but does not explicitly differentiate from calendar_search_events or calendar_get_event. The purpose is clear but lacks sibling comparison.

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?

No guidance on when to use this tool versus alternatives such as calendar_list_events or calendar_get_event. It does not mention prerequisites like needing a valid recurring event ID, or scenarios where this tool is appropriate (e.g., retrieving occurrences of a recurring event).

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