calendar_freebusy

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

With no annotations, the description carries the full burden of behavioral disclosure. It states the operation is a query ('Query free/busy info') and specifies the return content ('busy time blocks'), implying a read-only, non-destructive action. However, it does not mention authentication requirements, rate limits, or behavior with edge cases like empty calendars or invalid time ranges.

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 concise sentences with no redundant information. It front-loads the core purpose and immediately follows with the output type, making it easy to parse and clearly scoped.

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?

Despite having an output schema, the description lacks essential input context. With four parameters and zero schema descriptions, the agent cannot know how to construct a valid request (e.g., date formats, timezone handling, calendar selection). The description is too sparse for reliable tool use.

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 provides no parameter descriptions (0% coverage), and the description does not compensate. The phrase 'for calendars' hints at the calendars parameter, but there is no explanation of time_min, time_max, or timezone format. Agents are left to guess the expected input formats and semantics.

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 uses a specific verb ('Query') and resource ('free/busy info for calendars'), making the tool's purpose immediately clear. It also differentiates from sibling tools like calendar_get_events by focusing on availability rather than event details, and the phrase 'Returns busy time blocks' clarifies the output.

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 such as calendar_get_events or calendar_list_recurring_instances. There is no mention of prerequisites, exclusions, or specific scenarios where free/busy information is appropriate.

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