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

Beyond the annotations (readOnly, openWorld, idempotent), the description adds crucial behavioral context: it clarifies that an empty list means the query returned no zones, while `available: false` means the query did not execute, and it warns that ENAIRE's official viewer is authoritative. This goes well beyond the structured hints.

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 longer than average due to bilingual repetition, but it is well-structured: the first sentence states the core function, the second disambiguates from a sibling, the third explains result semantics, and the fourth adds authority. Every sentence adds value, though the dual-language duplication could be considered slightly 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 tool is relatively simple with one parameter and an output schema (presumably covering return structure). The description covers purpose, alternatives, edge-case interpretation, and authority. The only missing piece is the precise format of `bbox`, which is not provided in the schema or description, so the description is not fully complete.

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?

With schema description coverage at 0% for the single `bbox` parameter, the description must compensate. It mentions 'rectángulo' (rectangle) and 'bounding box', giving the conceptual meaning, but it does not specify the exact format (e.g., coordinate order, projection, delimiter). This is a minor but real gap for a tool with only one parameter.

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 explicitly states the tool returns UAS zone polygons within a bounding box, including type, vertical limits, and update date. It also clearly differentiates itself from `flight_requirements` as a map layer rather than a point verdict, making its purpose unambiguous and distinct from siblings.

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 provides explicit usage guidance: 'Es la capa que pinta un mapa, no un veredicto sobre un punto: para eso está `flight_requirements`' directly points to the alternative for point-based queries. It also explains how to interpret empty lists versus `available: false`, which is critical for correct usage.

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