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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so the safety profile is fully covered. The description adds the return characteristic of 'citable records and explicit verification status', which is mildly useful but largely duplicated by the output schema, and it omits pagination 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 tight sentences with zero filler. The core capability is front-loaded and the sibling pointer is placed last, which is exactly the right ordering.

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?

With an output schema present, return values needn't be re-explained, and the searchable-field list is helpful. But for a five-parameter tool the description leaves authority_status values (official/community/unreviewed) and pagination semantics undocumented, which are gaps an agent must guess at.

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 only 20% across five parameters. The description clarifies that the required query is matched against title/official title/description/topic, which is genuine added meaning for query, but limit, offset and authority_status receive no semantic explanation anywhere, and topic only inherits a terse schema note.

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?

Names a specific verb (search) and resource (Italian world/international days) plus the fields matched against (title, official title, description, topic), so an agent knows exactly what this returns. It hints at sibling separation via 'Use fetch for details' but doesn't distinguish itself from list_days or list_topics.

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?

'Use fetch for details' is an explicit routing rule for one alternative, which is real guidance. However, it says nothing about when to prefer this over list_days or list_topics, nor any when-not conditions, leaving the main sibling choice implied.

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