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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered; the description adds genuinely new behavioral facts the schema lacks — an implicit default range and a 62-day maximum. It still says nothing about pagination, multiple-calendar aggregation, or timezone handling.

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?

One sentence, zero waste, with the resource and the two operative constraints (default and cap) front-loaded.

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?

An output schema exists, so return values need no explanation, and the description covers the key sizing constraints for a read-only listing call. Remaining gaps — multi-calendar behavior and timezone — are minor but real for a 0%-coverage schema.

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 0% and the two date-time properties carry no descriptions, defaults, or bounds, so the description must compensate. It does supply the default window and maximum span, but never maps those semantics to the 'from'/'to' parameters individually, nor clarifies inclusivity or format.

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 names a specific resource (events from the connected Google calendars) and its scope (a date range), which an agent can distinguish from every email/campaign sibling. The verb is only implied by the tool name rather than stated, 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?

The default window (next 7 days) and hard cap (62 days) implicitly tell the agent how the tool is normally used, but there is no explicit when-to-use/when-not statement and no named alternative. With no calendar sibling to route away from, this is adequate but thin.

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