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

Annotations already declare read-only, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds genuine context beyond that: it returns a few live matches, resolves one place per call, and warns 'do not invent a handle', disclosing the fuzzy/lookup nature and a hallucination guard. Minor gap: it doesn't say what happens when no match is found.

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?

Front-loaded with the core action, followed by a compact usage clause and then imperative routing instructions. Every sentence carries actionable content; nothing is repeated from the schema or annotations.

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?

An output schema exists so return values needn't be explained in depth, and annotations cover safety semantics; the description still names the key returned fields and the follow-up tool chain. For a two-parameter lookup tool, nothing an agent needs in order to call it correctly is missing.

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%, so both query and page_size are already documented, and the description adds only marginal meaning via examples of accepted query forms (city, country, region, IATA). The 'one place per call' constraint is a useful clarification of query semantics, but page_size is left entirely to the schema — correct baseline of 3.

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 ('Resolve') and target resource ('Sorted destinations') with concrete input shapes (city, country, region, airport) and examples (paris, hanoi, IATA code). An agent can immediately distinguish it from siblings like get_destination_info or get_destination_weather.

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?

Explicit trigger condition: 'when the traveler names a place and you do not already have a sitemap handle'. It also routes post-resolution behavior precisely — get_destination_info for generic info, get_destination_weather only for weather/forecast/climate, get_recommended_destinations with airport_code for ranking — including an explicit 'not weather' exclusion.

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