Feriados nacionais

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

No annotations are provided, so the description carries the full burden. It discloses the scope (includes movable holidays based on Easter) but does not mention return format, error handling, side effects, or whether the operation is read-only. For a simple listing tool this is acceptable but incomplete.

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 one concise sentence that is front-loaded with the main action and resource. Every word earns its place, with no redundant or filler content.

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?

Given the simple nature (1 parameter, no output schema), the description covers the purpose but omits details about the return value structure (e.g., whether it returns dates, names, or objects). Without an output schema, the description should explain the output shape to be fully complete.

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 only parameter 'year' has a clear description. The tool description adds value by explicitly noting that the list includes movable holidays based on Easter, which explains why the year is required and how it affects results beyond the schema's basic type/range information.

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 clearly states the tool's function with a specific verb ('Lista' – lists) and a precise resource ('feriados nacionais obrigatórios de Portugal' – mandatory national holidays of Portugal) for a given year. It also distinguishes itself from siblings like is_holiday by focusing on a full yearly list rather than a single date check.

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 (for a given year) but does not explicitly state when to prefer this over alternatives, nor does it mention any exclusions or contrasting sibling tools. The context is self-evident for listing holidays, but the guidance is implicit rather than explicit.

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