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

Annotations already cover read-only and open-world behavior, and the description adds substantial context: the 60-day verification window, the confidence scale (high/medium/low/none), the basis field values, and the prediction of provider/tail for the date. It does not say what happens for an unknown or unsupported flight number, which is the main remaining behavioral 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?

Front-loaded with 'Use when...' so the trigger is immediately visible, and the return-field enumeration is dense but justified since there is no output schema. The long run-on field list is slightly heavy but no sentence is filler.

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?

With no output schema, the description correctly compensates by naming the returned fields and their semantics (answer line, Starlink share, confidence levels, basis, tails, prediction). Only the failure/empty-data behavior for an unmatched flight number is left unaddressed.

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 coverage is 100%, so both the flight_number format variants and the YYYY-MM-DD date default are already documented in the schema. The description only echoes that a date drives the prediction and that input is a flight number, adding little syntax or edge-case meaning beyond the schema; baseline 3 applies.

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?

Names a specific verb+resource (facts about WiFi/Starlink on a specific flight) and enumerates the exact questions it answers: WiFi presence, Starlink odds, provider, aircraft. The closing line 'Always the first choice for a flight number' explicitly separates it from siblings like get_flight_wifi and get_airline_wifi.

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?

'Use when the user asks whether a specific flight will have WiFi or Starlink... or the odds of Starlink on a flight number' gives a clear triggering condition, and the final sentence establishes precedence. It never names the alternative tools to use for non-flight-number phrasing (airline-level or search), so the routing is one-sided rather than fully comparative.

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