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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds important behavioral context: it accepts up to 50 identifiers mixing three types, returns per-identifier results with a found flag, and clarifies that missing results are not errors. This goes beyond the annotations by explaining the response semantics and error interpretation, though it does not disclose any rate limits or authentication requirements beyond what is typical.

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?

The description is a single, well-structured paragraph that is front-loaded with the core purpose, includes key usage details (limit of 50, mixing types, response structure), and ends with a practical note about missing results. No redundant information; every sentence adds value.

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 tool is relatively simple with 3 optional parameters and no output schema, but the description is quite complete: it explains the input types, the limit, the response format per identifier, and the interpretation of missing results. It does not address pagination (not needed) or error cases, but given the simplicity and annotations, this is close to complete. Small deduction for lacking a concrete example of the identifier formats (e.g., exact hex format).

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 0% (property names are descriptive but no descriptions in schema). The description adds semantic meaning by explaining the three types of identifiers (hexes, callsigns, registrations) and their formats, but it does not provide detailed syntax examples or constraints (e.g., string length, case sensitivity). It adds value, but the description is not exhaustive; however, the parameter semantics are fairly self-explanatory from the names and the description compensates partially.

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 clearly states the tool provides live position of specific aircraft by registration, ICAO hex code, and/or callsign. It distinguishes itself from siblings by specifying the exact identifiers used and the response structure, making it clear this is for querying specific aircraft rather than airport/nearby/closest types.

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?

The description explains when to use this tool (to query specific aircraft by identifier) and implicitly differentiates from sibling tools like flightradar_closest and flightradar_nearby which would cover broader spatial queries. It also notes a limitation (aircraft not found may be out of coverage or not transmitting ADS-B), but does not explicitly state when not to use it versus alternatives, so a small deduction.

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