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

Annotations only supply destructiveHint=true, so the description usefully adds the downstream behavioral consequence that auto-scheduling will skip the employee during the window, plus the underlying API route. It does not state permission requirements, overlap handling, or how to undo the record, keeping it short of a 5.

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 tight sentences plus the endpoint reference; the core verb and the one-off/recurring distinction are front-loaded with no filler.

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 5-parameter write tool with a nested recurrence object and no output schema, the description covers the key decision (one-off vs recurring) and the scheduling impact. It omits return/ID behavior and validation constraints, but nothing critical to invoking it correctly is missing.

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 coverage is 100%, and the description's recurrence example ('FREQ WEEKLY, INTERVAL 1, BYDAY MO') and 'Omit for a one-off block' largely restate what the nested schema properties already document. Baseline 3 is appropriate since the schema carries the parameter burden.

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?

Specific verb+resource: 'Record a time an employee cannot work', immediately scoped to one-off vs recurring blocks. It clearly distinguishes itself from the read-side sibling deputy_get_employee_unavailability and from shift/leave tools by naming the concrete effect on availability.

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?

Usage is implied rather than stated: 'Auto-scheduling then skips them' tells the agent why the record matters, but there is no explicit when-to-use versus alternatives such as deputy_create_leave_request, which also blocks an employee's time. No exclusions or prerequisites are given.

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