calendars_get_slots

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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, covering safety and idempotency. The description adds no behavioral context beyond 'Get Free Slots'—it does not mention what constitutes a free slot, how results are structured, pagination, or edge cases. With annotations present, the bar is lower, but the description still fails to provide any additional useful behavioral information.

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 a single short sentence, which is concise in length, but it is under-specified. It does not earn its place because it omits essential information. The structure is acceptable, but the extreme brevity leaves the description useless beyond a minimal label.

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 tool with six parameters and no output schema, the description is severely inadequate. It fails to explain the return format, the meaning of free slots, the required calendarId context, timezone handling, or the 31-day limit (even though that is in the schema). An agent cannot confidently invoke this tool based solely on the description without inferring from the schema and tool name.

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 all six parameters already have descriptions in the input schema. The description does not add any parameter-specific meaning beyond what the schema provides, such as clarifying the 31-day date range constraint or explaining the difference between userId and userIds. Since the schema already documents the parameters thoroughly, a baseline of 3 is appropriate.

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 'Get Free Slots' states a verb and a resource, giving a basic sense of the operation. However, it does not specify that these are calendar free slots or distinguish this from sibling tools like calendars_get_blocked_slots or calendars_get_calendar_events. It is not a tautology but lacks the specificity needed for an agent to clearly understand the tool's unique purpose without examining sibling names.

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 provides no guidance on when to use this tool versus alternatives. There is no mention of context, prerequisites, or situations where this tool should be preferred. An agent would have no idea why to pick this over calendars_get_blocked_slots or other calendar-related tools.

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