Variflight MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively describes key behavioral traits: the requirement for valid IATA codes, date format constraints, and the interaction with the getTodayDate tool for date handling, though it lacks details on output format, error handling, or rate 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 appropriately sized and front-loaded, with each sentence earning its place by providing essential information without redundancy. It efficiently covers purpose, parameter usage, date handling, and code validation in a structured manner.

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 complexity of 5 parameters, no annotations, and no output schema, the description does well by covering parameter semantics, usage guidelines, and behavioral aspects like date handling. However, it lacks details on the return format (e.g., what data is included in flight results), which is a minor gap in completeness.

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 description coverage is 100%, so the baseline is 3. The description adds significant value by explaining the semantic difference between dep/arr (airport codes) and depcity/arrcity (city codes), providing usage rules for cities with multiple airports, and reinforcing date format and tool dependencies, elevating it above the baseline.

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 the tool's purpose with a specific verb ('Search for flights') and resource ('between airports or cities by date'), and distinguishes it from sibling tools like 'searchFlightItineraries' and 'searchFlightsByNumber' by specifying it searches by departure/arrival locations rather than itineraries or flight numbers.

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 provides explicit guidance on when to use specific parameters (depcity/arrcity vs. dep/arr based on city airport multiplicity) and when to use an alternative tool ('For today's date, use the getTodayDate tool'), offering clear context and exclusions.

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