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

With no annotations, the description carries the full burden. It discloses the useful default (fecha = hoy) and that the conversion goes between UI and UYU, but says nothing about which UI source/quote is used, whether the result is rounded, or how errors (e.g. a non-business date) are surfaced. For a financial conversion tool this is a meaningful gap.

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 sentence with no filler; the verb, the two units, and the date default are all packed in without redundancy.

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 3-parameter tool with no output schema and no annotations, the description covers the core operation but omits what the return value looks like (converted amount plus the UI value used?) and the exact meaning of the 'de' direction. Adequate but leaves the agent guessing about the response shape.

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 clarifies the 'fecha' default (hoy) and the direction implied by 'de' (UI vs UYU), which the bare enum does not spell out, but it never defines 'monto' semantics (positive amount, rounding) beyond the schema's exclusiveMinimum. Partial compensation only.

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 (convierte) and the resource (un monto entre Unidades Indexadas y pesos uruguayos), so the agent knows this is a currency/unit conversion tool, not a lookup. It does not explicitly contrast itself with siblings like uy_ui or uy_ui_historico, but the verb+resource combination is distinctive enough to select correctly.

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 guidance at all: no mention of when to prefer this over uy_ui (value lookup) or uy_ui_historico (historical series), and no stated preconditions. The conversion intent is only implied by the verb, leaving the agent to infer routing from sibling names alone.

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