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

Annotations already declare readOnlyHint and openWorldHint, and the description adds real value beyond them: fuzzy/typo-tolerant matching, cross-language name lookup, and what the results contain (guide URLs, IATA codes). It does not cover result volume or the effect of the limit parameter, which is the only remaining gap.

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 dense sentences with zero filler. The core behavior comes first and the downstream hand-off second, which matches how an agent would reason about the call.

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 carries the return-value burden and does so by naming URLs and IATA codes. It stops short of describing result ordering or how limit caps the list, a minor omission for a 3-parameter search tool.

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 67%, with query and locale already documented. The description adds semantics the schema lacks: matching is typo-tolerant and works in any language, and the IATA codes returned are intended to feed find_flight_prices. The limit parameter is left unaddressed in both places.

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 and resource ("Finds countries and cities by name") plus the distinctive matching traits (any language, typo-tolerant). It also names the downstream consumer, find_flight_prices, which separates it cleanly from the eSIM siblings.

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?

Gives clear usage context by positioning the tool as the lookup step before find_flight_prices, and the query example hints at multilingual input. It never states when not to use it, e.g. versus list_esim_countries, so it falls short of explicit alternatives.

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