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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is fully covered. The description adds the API path and the shape of the returned records, which is useful given no output schema, but it says nothing about pagination behavior, rate limits, or empty-result 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?

Three short sentences, front-loaded with the primary purpose followed by filtering dimensions and the API reference. No filler and no redundancy; every clause carries information.

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, fully-optional-parameter list tool with no output schema, the description covers what is returned and how to narrow it, which is sufficient to call it correctly. Minor gaps around pagination and result ordering are handled by the schema, so completeness is good.

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 every parameter (page, order_by, per_page, child_ids, contact_ids, ministry_ids, starts_after, starts_before) is already documented in the schema. The description restates the person/ministry/date filtering dimensions at a high level but adds no syntax, id-format, or boundary detail beyond what the schema provides, which matches the baseline for high 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?

States a specific verb (List) plus resource (rota unavailability) and even enumerates the returned fields (person, description, start/end) and the underlying endpoint. It is unambiguous, though it does not explicitly differentiate itself from any sibling because none of the listed siblings cover rota/unavailability data.

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 its usage via "Filter by person, ministry or a date window," which tells an agent the three axes available for narrowing results. However, it never states when to reach for this tool versus alternatives, nor any exclusions or prerequisites, so guidance is only implied.

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