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

With no annotations, the description carries the full behavioral burden. It usefully discloses the 366-day maximum and the default-to-today behavior when `hasta` is absent, but it does not mention read-only status, permissions, rate limits, or error handling for out-of-range requests.

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 short sentences with zero filler; the core behavior is front-loaded and the default rule follows immediately. Every sentence earns its place.

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 simple data-retrieval tool with no output schema and no annotations, the description explains the data and range constraint but does not describe the return shape (e.g., date/value pairs) or error behavior. Adequate to call, but not fully complete.

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%, so the description must compensate. It explains that two dates define the range, that `hasta` defaults to today when omitted, and that the range is capped at 366 days — adding substantial meaning beyond the bare date-pattern 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 the resource and scope precisely: daily Unidad Indexada series between two dates. The historical nature is implied by the date-range constraint, but the description does not explicitly distinguish this tool from the sibling uy_ui (current value), so it stops short of a 5.

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?

No guidance on when to use this tool versus siblings such as uy_ui or uy_cotizaciones. It only documents the default behavior when `hasta` is omitted, which is a parameter rule rather than a usage rule.

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