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

With no annotations to lean on, the description carries the burden and does disclose the output shape (uppercase IATA code) and a hard constraint against fabricating codes. It omits behavior for unresolvable or ambiguous names, so it is strong but not exhaustive.

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 short sentences, front-loaded with the transformation, then the ordering rule, then the constraint. No filler; every sentence earns its place.

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?

For a single-parameter resolver with no output schema, the description supplies the missing return contract (uppercase IATA code) and call ordering. The only gap is unspecified handling of unknown or ambiguous queries.

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% and the schema already explains 'query' as a city or partial name. The description reinforces that input may be spoken-style, adding slight value, but there is little beyond the schema to convey.

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 precise verb+resource (turn a spoken city name into an uppercase IATA code) and names the exact output contract other tools expect. It is clearly distinguishable from find_cheapest_fare and list_routes_from.

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?

Explicitly tells the agent when to call it (before find_cheapest_fare, whenever uncertain of a code) and adds a negative rule ('Do not invent codes'), which routes behavior away from hallucinating codes.

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