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

Annotations already declare readOnly, idempotent, and non-destructive, so the description only needs to add behavioral context. It does add useful scope (comparison across every tracked airline) and an external fallback, but the parenthetical 'nonstop' conflicts with the schema's max_stops parameter, and 'Starlink odds' is left undefined.

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 with the trigger first, then the behavior, then the special-case routing. There is no filler, and the most decision-relevant information is front-loaded.

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?

All parameters are documented and annotations cover the safety profile, but there is no output schema and the description never states what the returned itinerary or odds look like, nor how 'full-coverage' versus 'partial baselines' are presented. The ambiguous 'nonstop' wording also leaves a gap about how connecting itineraries are handled.

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 every parameter already has a clear description with examples and bounds, so the description need not repeat parameter details. The 'X to Y' phrasing maps only trivially to origin and destination, providing no additional semantic value beyond the 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 pairs a concrete trigger ('what's the best way to fly X to Y with Starlink?') with a specific behavior ('Compares Starlink odds... across every tracked airline'), so it goes beyond merely restating the title. It stops short of 5 because it never names a sibling tool such as predict_route_starlink or search_starlink_flights, and the 'nonstop' parenthetical is ambiguous.

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 gives an explicit when-to-use trigger and a special-case routing rule for multi-stop UA itineraries (connect to unitedstarlinktracker.com/mcp). However, it does not enumerate the sibling tools as alternatives, leaving the agent to infer when this tool should be preferred over the other Starlink prediction tools.

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