Get a specific flight

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

With no annotations, the description carries the full burden. It discloses that the tool returns a single best match and acts as a wrapper, but it omits details on error behavior, what happens when no match is found, or how 'best match' is determined, leaving some ambiguity.

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?

The description is two sentences, front-loaded with the core purpose and followed by a useful context statement about being a wrapper. No unnecessary words.

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 simple lookup tool with three parameters and no output schema, the description covers the essential elements: what it does, how it relates to search_flights, and its single-match behavior. Missing error-case details, but overall sufficient for the tool's simplicity.

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?

The schema already documents airport and flightNumber, and direction has an enum but no description. The description adds little to parameter understanding—it only mentions 'by number at an airport' and doesn't clarify the role of direction or the requirement for all three parameters. With 67% schema coverage, it doesn't compensate for the missing direction explanation.

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?

The description clearly states 'Find one flight by number at an airport' with a specific verb and resource. It distinguishes itself as a convenience wrapper over search_flights that returns a single best match, making its unique purpose evident.

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?

It explicitly identifies itself as a wrapper over search_flights and notes that it returns 'the single best match', implying it should be used when a specific flight is needed rather than a broad search. However, it doesn't provide explicit when-not-to-use guidance or compare with list_airports.

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