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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds useful context that the result includes working hours and busy times over a date range, but it does not disclose timezone handling, pagination, or how optional filters such as withSource affect behavior.

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 efficient sentence with the core scope front-loaded. It contains no filler or repetitive wording.

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 availability tool, the annotations cover safety, and the description indicates the returned content. However, with five parameters, 40% schema coverage, and no output schema, the definition leaves meaningful gaps around optional filter semantics and result details such as timezone or pagination.

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 only 40%: dateFrom and dateTo are documented in the schema, but username, withSource, and eventTypeId are not explained. The description mentions username and date range but adds no detail on the optional parameters or username format, so it does not compensate for the low schema coverage.

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 a specific verb and resource: showing working hours and busy times for a Caly username within a date range. It is clear enough to distinguish the operation from generic calendar reads, but it does not explicitly differentiate itself from close siblings such as get_busy_times, get_calendar_freebusy, or find_available_slots.

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 states what the tool does but provides no explicit when-to-use guidance, prerequisites, or alternatives. It does not tell the agent when to choose this over get_busy_times, get_calendar_freebusy, find_available_slots, or get_team_availability.

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