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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description's only behavioral addition is the 'stacked-series style payload' hint about output shape, which is partly redundant with the existing output schema.

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?

One sentence, front-loaded with the resource and granularity, and nothing superfluous. It is arguably too sparse rather than verbose.

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?

The output schema absolves the description of explaining return values, and annotations cover safety. However, with a crowded sibling set and no differentiation or usage routing, an agent still lacks enough to confidently choose this tool over Flight_flights_by_year.

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 single parameter has 0% schema description coverage, but the description does clarify that the id refers to an aircraft and that results are scoped to it. That is minimal added meaning over the self-explanatory parameter name.

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 resource (arrival-country flight counts), a granularity (per-year), and a scope (one aircraft id), which is enough to distinguish it from Flight_flights_by_year and Flight_airport_arrivals_by_country in broad terms. The 'stacked-series style payload' phrasing is a shape hint rather than a purpose statement, but the core verb+resource is clear.

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 when-to-use guidance and no mention of alternatives, despite several closely related siblings (Flight_flights_by_year, Flight_airport_arrivals_by_country). The agent must infer the selection criteria from the data shape alone.

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