ar_uvaValor de la Unidad de Valor Adquisitivo del BCRA para una fecha (default hoy), o la serie diaria entre desde y hasta (máx. 366 días).
This tool declares no required parameters. Add optional parameters from the input schema as needed.
{
"id": 1,
"jsonrpc": "2.0",
"method": "tools/call",
"params": {
"arguments": {},
"name": "ar_uva"
}
}| Name | Required | Description | Default |
|---|---|---|---|
| desde | No | ||
| fecha | No | ||
| hasta | No |
Changes observed during successful MCP inspections.
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 default (hoy) and the hard cap of 366 days for series requests, but says nothing about permissions, return shape, or what happens on invalid/out-of-range dates.
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 well-structured sentence, front-loaded with the resource and followed by the two operating modes and the constraint. No filler.
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 tool with no annotations, no output schema, and 0% schema coverage, the description covers modes, default, and the 366-day limit. It still leaves date format and param interaction (can fecha coexist with desde/hasta?) unexplained, so it is adequate but not 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, and it does map roles: 'fecha' = single date (default today), 'desde'/'hasta' = series bounds. It omits the required YYYY-MM-DD format and whether the three params are mutually exclusive or combinable, so it only partially fills the coverage gap.
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?
The description states a specific resource (the BCRA's Unidad de Valor Adquisitivo value) and two concrete modes: a single-date lookup defaulting to today, or a daily series across a range. It is clear and distinguishable in intent from the conversion sibling ar_uva_convertir, though it never explicitly names that alternative.
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?
It implies when each mode applies ('para una fecha' vs 'la serie diaria entre desde y hasta'), which is useful selection guidance within the tool. However, it gives no guidance on when to prefer this over ar_uva_convertir or the other ar_* value tools, leaving the cross-tool choice to inference.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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