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

No annotations are supplied, so the description carries the full burden. It does add genuinely useful behavioral context — the '20 credits' cost and the bounded lookback window — but says nothing about the shape of the returned positions, whether the list is ordered, or what happens for an unknown or invalid hex.

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?

Two short sentences, front-loaded with the resource and scope, ending with the cost note. Almost nothing is wasted, though the parenthetical range duplicates schema constraints and could have been spent on return-format guidance instead.

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 two-parameter tool with no annotations and no output schema, the definition covers identifier format, time window, and cost, but leaves the agent guessing about return contents (timestamps, altitude, ordering) and credit scaling with the minutes window. Adequate to invoke, thin for interpreting results.

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 0%, so the description must supply meaning, and it does add one real thing: 'icao24' is a Mode-S hex with a concrete example ('a1b2c3'). The 'minutes (5 to 1440)' restates the schema's minimum/maximum/default rather than explaining semantics such as whether a larger window costs more credits or returns coarser points.

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 ('positions of one aircraft') and a clear time scope ('over the last minutes'), which is enough to distinguish it from aircraft_info (static metadata) and flight_history. It stops short of naming any sibling explicitly, so the differentiation is inferred from the resource rather than asserted.

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?

Usage is only implied: an agent can infer this is the tool to call when it has a Mode-S hex and wants a recent track, but the description never says when to prefer it over live_aircraft_near, aircraft_overhead, or flight_history, nor does it state prerequisites such as needing a valid hex first.

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