calendar_free_slots

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

With no annotations, the description must fully disclose behavioral traits. It covers busy sources (selected calendars), ignored event types, and defaults. However, it does not describe the output format (e.g., list of time slots), edge cases (if no free slots), or rate limits. The description is somewhat transparent but lacks completeness on return structure.

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 two sentences, front-loaded with purpose and example. Every sentence adds value: the first gives the core function and use case, the second explains default behavior and date format. No fluff or redundancy.

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 8 parameters (1 required), no output schema, and no annotations, the description is fairly complete: it explains date range, daily windows, calendar selection, and handling of all-day/free events. However, it omits the output format (what does a free slot look like?) and any pagination or limit details. This is a moderate gap.

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 baseline is 3. The description adds context on default behavior (e.g., all-day events ignored) but the parameter descriptions in the schema are already detailed. No significant additional meaning beyond schema is provided.

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 tool finds free time slots across calendars in a date range, with an example use case ('plan a call or a week'). The verb 'finds' and resource 'free time slots' are specific. It implicitly differentiates from siblings (calendar_calendars, calendar_events) by focusing on availability, not listing calendars or events.

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 explains default behaviors (ignoring all-day/free events) and recommends date format, but does not explicitly state when to use this tool versus calendar_events or calendar_calendars. No alternatives or exclusions are mentioned. Usage context is implied but not comparative.

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