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

Annotations already establish the safe read-only, idempotent, closed-world profile, so the bar is lower; the description still adds real value by disclosing the assumed reference rate (12,5% E.A.) and that the result is 'orientativa'. It does not say how it behaves if neither monto nor ingreso is supplied, but the core behavioral context is present.

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 tight sentences: the first front-loads the calculation, rate assumption and both modes; the second supplies usage examples. No filler, and the most decision-relevant content leads.

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, four fully documented parameters, and complete annotations, the description supplies everything an agent needs: what is computed, the rate basis, the indicative nature, and which input drives which mode. Nothing material for correct invocation is missing.

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%, so every parameter (including the rol enum) is already documented in the schema. The description explains the two input modes and their relationship, but this largely restates what the schema descriptions already convey, 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 precise verb+resource ('Calcula la cuota mensual orientativa de un crédito hipotecario en Colombia') and even covers the two operating modes (payment from monto+plazo, or max amount from ingreso). The purpose is unmistakable, though it never explicitly names or contrasts itself with the siblings like perfilar_negocio or radicar_con_lqn.

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 concrete when-to-use guidance via sample queries ('¿cuánto paga por 200 millones a 20 años?', '¿cuánto le prestan ganando 5 millones?'), which maps user phrasings to the tool. It stops short of stating when not to use it or pointing to an alternative sibling for other mortgage scenarios.

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