find_free_time

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

Since no annotations are provided, the description carries the full burden of behavioral transparency. It discloses important behaviors: openings reported at full length, not trimmed to duration; events not counted as busy (free, cancelled, declined), and all-day events not counted but listed separately. The only missing detail is the exact return format, but the description covers key edge cases.

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 well-structured and appropriately sized. It is front-loaded with the core purpose, then provides usage guidance, then behavioral details. Every sentence earns its place, covering purpose, usage, alternative, and behavioral nuances without redundancy or fluff.

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 parameter count of 8, no output schema, and no annotations, the description is quite comprehensive. It addresses key behavioral edge cases (full-length reporting, non-counted events, all-day events) that are not apparent from the schema. Minor gap: it does not explain the default time range or how openings are returned (e.g., start/end times), but the input schema covers defaults. Overall, it provides sufficient context for an agent to use the tool effectively.

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 schema already has 100% coverage for parameters, so the baseline is 3. The description adds value by explaining the semantics of the 'duration' parameter in relation to output behavior (full length not trimmed), which informs interpretation of the duration input. It also clarifies the treatment of all-day events, which relates to how parameters like includeWeekends and dayStart/dayEnd might interact. The description does not repeat parameter descriptions but adds contextual meaning.

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 open slots on the user's calendars, specifying the requirement of sufficient length. It distinguishes from search_events, which is about existing events, by noting the intended use for availability queries and pre-event planning. The verb 'find' is specific to the resource 'open slots' and the scope is user's calendars.

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 explicitly provides when to use the tool: to answer 'when am I free for X' or to pick a time before calling create_event. It also gives an explicit alternative: 'To ask what is already scheduled, use search_events instead.' This is clear usage guidance with exclusions and alternative, matching the highest benchmark.

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