Time-off balances

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false, so the safety profile is covered. The description adds behavioral context beyond that: the temporal dimension ('as of a date') and the future-projection behavior, plus the response scope (every assigned type, year-to-date used). It doesn't mention auth or rate limits, but for a read-only tool with full annotation coverage this is acceptable.

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?

Two sentences, zero filler. The core purpose is front-loaded, followed by a single, high-value usage note. Every word contributes.

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 2 params and no output schema, the description sufficiently conveys the purpose, the parameter behavior, and the expected data (balances per type, ytd used). It could list return fields in more detail, but the simplicity and annotations make this an adequate level of completeness.

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?

Input schema coverage is 100%, so the baseline is 3. The description adds meaning above the schema by explaining that the asOf date can be a future date to project the balance, and clarifies the balance includes year-to-date usage, which goes beyond simple schema field descriptions.

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 states the specific verb 'Get' and the resource: 'one employee's time-off balances for every assigned type as of a date, including amount used year-to-date.' The explicit single-employee scope differentiates it from sibling tools like 'time off requests' or company-wide overviews.

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 implies usage (when you need a single employee's balance history) and provides a useful tip for the asOf parameter ('Use a future date to project the balance'), but it does not explicitly state when to prefer this tool over siblings such as 'bamboohr_vacation_overview', and no exclusions are given.

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