Find double bookings

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

With no annotations, the description carries the behavioral disclosure burden and does substantial work: it reveals pair-wise output, collision minutes, all-day event separation, calendar scoping, and a 31-day free limitation. It stops short of discussing timezone handling or exact output shape, but the core behavior is transparent.

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 compact and front-loaded, placing the key semantics in the first clause and adding short, useful qualifications. The 'Free: 31 days' fragment is cryptic, but overall there is no wasted content.

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 read-only lookup with three well-schema-documented parameters, the description supplies the essential selection and behavior information, including the free_busy alternative. Without an output schema, it could specify the returned pair structure more concretely, but an agent can still select and invoke the tool correctly.

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 from, to, and calendar are already documented with formats and defaults. The description adds little beyond restating the calendar scope ('unless you name one') and an ambiguous 'Free: 31 days' constraint, staying at the high-coverage baseline.

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 the operation directly ('Find double bookings') and defines it precisely: every pair of timed events that overlap, with collision minutes, across all calendars unless one is named. This clearly distinguishes it from event listing and free_busy sibling tools.

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?

It provides a clear use case and explicitly routes to free_busy for gaps ('free_busy shows gaps'), giving the agent a useful alternative. It does not enumerate when not to use other event/calendar tools, but the overlap-vs-gaps framing is enough for correct selection.

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