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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is fully covered in structured data. The description adds the useful behavioral detail that omitting the year yields the next 10 upcoming holidays, but says nothing about ordering, format, or what happens for unsupported years.

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?

A single front-loaded sentence that names the resource first and the scope second, with no filler. Nothing could be removed without losing supported-year 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 one-optional-parameter, read-only lookup with rich annotations, the definition covers everything needed to select and invoke it. Only the shape of the returned holiday list is unstated, which is minor for a simple enumeration tool with no output schema.

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 single parameter's description already states 'Optional: 2026, 2027 or 2028. Leave out for the next 10 upcoming'. The tool description merely restates this ('or the next upcoming ones') without adding meaning such as behavior on out-of-range years.

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 gives a specific verb and resource ('List Ireland's public holidays') plus the exact supported scope (2026, 2027, 2028, or upcoming). An agent can distinguish this from siblings like public_holiday_pay_ireland, which is about pay rules rather than enumerating holidays, though the description never says so explicitly.

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 by the year/upcoming dichotomy rather than stated as guidance: pass a year for a specific list, omit it for upcoming holidays. There is no explicit when-to-use versus alternatives (e.g., public_holiday_pay_ireland) and no when-not-to-use guidance.

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