Search Flights

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds output details (best_flights, other_flights, Google Flights URL), but an output schema exists, reducing the need for that. It discloses no additional behavioral caveats such as rate limits, failure modes, or result-size limits.

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 front-loaded with a one-sentence purpose, followed by a compact Args list and a brief Returns note. Every line contributes useful information, and the length is justified by the 10-parameter surface area.

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?

Given the high parameter count and complete lack of schema descriptions, this tool description is sufficiently complete for an agent to invoke it correctly. It covers all parameters, defaults, filters, and return shape, leaving no critical ambiguity.

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 0%, but the description fully compensates by explaining every parameter with examples (IATA codes), format (YYYY-MM-DD), defaults, and enumerated meanings (stops, travel_class, sort_by, currency). This adds significant value beyond the bare input schema.

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 opens with 'Search for flights on a specific route and date,' which clearly identifies the verb, resource, and core scoping criteria. This distinguishes it from the sibling mcp_get_booking_options by focusing on the flight search itself rather than booking options.

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?

The description gives clear context for when to use the tool: searching flights on a route and date. It does not explicitly mention the sibling alternative or provide exclusions, but the use case is unambiguous and easy for an agent to apply.

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