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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds substantive behavior beyond that: results are straight-line distances in km, not travel times or routes, and only published hotels qualify — exactly the kind of clarification that prevents misuse.

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 short sentences with zero redundancy; the scope and category list come first and the critical disambiguation ('not times or routes') is front-loaded at the end where it lands clearly. Nothing could be removed without losing 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?

With no output schema, the description must carry the return semantics, and it does so at least partially by specifying the distance metric in km. Small gaps remain: it does not say whether results are sorted by distance, whether the hotel must exist, or what happens when it is not found, but for a simple three-parameter read tool this is close to sufficient.

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 hotel, tipo and massimo are already documented, including the enum values and the 1-20/default-10 bound. The description mentions the categories that match the tipo enum but adds no new meaning for the hotel identifier or the maximum parameter; baseline 3 applies.

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 resource and scope: places near a published hotel, with the categories enumerated and the metric defined (straight-line distance in km). It is clearly distinct from the sibling tools (hotel list/detail/booking), though it does not name or route to any alternative.

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 phrasing and by the explicit negative clause 'Non sono tempi né percorsi', which tells the agent not to use this for travel times or routes. There is no positive when-to-use guidance, no mention of prerequisites beyond 'published hotel', and no named alternatives.

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