Find an affordable available flight for a specific route by providing departure and arrival cities. Use it to search routes and compare fares.
Get the cheapest available flight for a specific route.
| Name | Required | Description | Default |
|---|---|---|---|
| arrival | Yes | Arrival city | |
| departure | Yes | Departure city |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden. It does not disclose whether the result is always a single flight, what happens when no flights exist, whether dates are considered, or any rate limits. For a query tool with zero annotation coverage, this is a significant 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?
A single, efficient sentence with no wasted words. The purpose is front-loaded and immediately clear.
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 tool with no annotations, no output schema, and no behavioral details, the description is insufficient. It should explain return behavior, date handling, or how 'cheapest' is determined, especially given the array of sibling flight tools.
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%, with both departure and arrival documented. The description adds no format details or meaning beyond the schema. Baseline 3 is appropriate when the schema does the heavy lifting.
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 (get) and resource (cheapest available flight) plus route scope. It distinguishes itself from search_flights by emphasizing cheapest, though it doesn't name the sibling explicitly. Clear but lacks direct sibling differentiation.
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?
No explicit when-to-use or when-not-to-use guidance. The description implies filtering for lowest price but doesn't state when to prefer this over search_flights or other alternatives. No exclusions or conditions are provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.