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

With no annotations, the description carries the full burden; 'Consulta' implies a read-only lookup, but read-only status, auth needs, and rate limits are never stated. It does add genuinely useful behavioral context the schema lacks: the real defaults (last 30 days / today) and the date format, since the schema only shows empty-string defaults.

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?

A single front-loaded purpose sentence followed by a compact Args block; nothing is padded. The Args block is slightly redundant with the schema but justified given the schema's empty defaults.

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?

For a two-param read-only date-range lookup with no output schema, the definition supplies everything needed to invoke it correctly: resource, units (soles per dollar), format, and defaults. Return-shape details are a minor gap that does not block correct invocation.

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 0% and both params have useless empty-string defaults in the schema, so the description must compensate — and it does, giving the YYYY-MM-DD format and the effective default for each of desde and hasta. It stops short of saying whether the range is inclusive or how wide a range is allowed.

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: queries the SBS 'venta' exchange rate (soles per dollar) from the BCRP, which clearly separates it from the contrataciones and norma_* siblings. However, it never distinguishes itself from serie_bcrp, the other BCRP-data sibling, so an agent cannot tell which one to reach for.

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?

There is no when-to-use or when-not guidance, no mention of alternatives, and no prerequisites or rate-limit notes. The only implied usage is 'call it to get an exchange rate for a date window', which the agent must infer from the description alone.

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