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

Annotations already declare readOnly, idempotent, closed-world and non-destructive, so the 'sin efectos secundarios / determinista' sentence mostly duplicates structured data. However, the description adds hard limits absent from annotations: 64 KB JSON input, 1 s per call, 1 MB result — genuinely new operational context.

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?

Content is well front-loaded (purpose first, then when/not-for, then effects and limits), but the full Spanish text is repeated verbatim in English, roughly doubling length without adding information. Useful, but half the tokens are redundant for any single reader.

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?

Output schema exists, so explaining return values isn't required, and annotations cover the safety profile. With purpose, routing, determinism and resource limits all present, an agent has everything needed to call it correctly.

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?

Single parameter with 100% schema description coverage (type, 1-12 length bounds, example), so the schema carries the burden and the baseline is 3. The description mentions geohash implicitly only through precision-12 encoding talk in the exclusion clause; it adds no syntax or format guidance for the input itself.

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 verb and resource ('Decodifica un geohash') plus the exact output contents (center point, bounding box, error margins), which no sibling provides. An agent can distinguish it from geohash-encode and geohash-neighbors without opening a schema.

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?

Explicit 'Cuándo' clause lists the downstream computations that justify the call (coordinates, distances, bearings, areas), and 'No para' names the sibling geohash-encode with its precision 1-12 / cell-size behavior. Both the use case and the exclusion are stated.

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