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

Goes well beyond the annotations by resolving the apparent write-vs-read tension: it states it does not charge, returns an exact amount plus an x402 endpoint, and prices at the blue-dollar rate of the day against the ARS 45.000/mes list price. That is exactly the behavioral context an agent needs to avoid assuming a payment is executed.

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?

Purpose and the no-charge caveat are front-loaded, but the middle is a long semicolon-chained list of PRO benefits (sello ★, remates resaltados, newsletter, panel de visitas, cruce Cañuelas) that mostly sells rather than informs tool selection. Two sentences carried by that list do the work of one.

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 usefully says what comes back (amount and x402 endpoint), what the pricing basis is, and what the two parameters mean. It does not say what happens on an invalid slug, or whether a follow-up call completes activation after payment.

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 coverage is 100%, so the baseline is 3; the description still adds the provenance of 'slug' (directorio entry) and the sibling tool to resolve it, which the schema does not say. The 'meses' range and default merely restate the schema.

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 ('Cotiza y explica cómo activar PRO Consignataria pagando en USDC'), and the key sentence 'Esta tool NO cobra: devuelve el monto exacto y el endpoint x402 para pagar' pins down what the call actually does versus what its name implies. The long benefits enumeration occupies most of the text and slightly blurs whether this is a marketing blurb or a transactional quote tool.

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 routing rule for the required parameter ('usá find_livestock_broker si no lo sabés'), which is the most likely failure mode for an agent. No guidance on when *not* to use it, or on how it relates to the /planes web page beyond the price equivalence.

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