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

Annotations already declare readOnlyHint, idempotentHint and non-destructive, so safety is covered. The description adds genuinely new behavior: the score is derived from BORME events and is gated behind the 'Plan Business' tier — a meaningful access constraint an agent would otherwise not know.

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?

Three tight sentences: purpose, evidence sources, then the usage trigger. Front-loaded and waste-free, though the 'Plan Business' note appended at the end reads slightly as an afterthought rather than an integrated constraint.

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?

With no output schema, the description should explain what comes back; it does so partially (a risk level plus its reasons) and names the underlying signals, which is enough to call the tool correctly. The score scale and behavior when a company has no BORME data remain unstated, a minor gap.

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 100% and the single cif parameter is fully documented in the schema (format, length, examples, spacing tolerance). The description adds nothing about the parameter, so the baseline 3 applies.

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 (nivel de riesgo de una empresa) plus its derivation source (publicaciones en el BORME) and enumerates the event types that feed the score, which clearly differentiates it from get_borme_history (raw history) and verify_company.

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?

Gives an explicit decision context — 'Úsala antes de dar crédito o firmar con un proveedor' — which tells the agent exactly when this tool is the right call. It does not name an alternative or state when NOT to use it, which keeps it out of the 5 tier.

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