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

Annotations declare readOnlyHint=true, which the description aligns with (no side effects mentioned). The description adds context that it's free and returns exchange rates/factors, but it doesn't disclose potential data gaps for certain months or the behavior when no data is available (e.g., error handling), which an agent might need to know. No contradiction with annotations.

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?

The description is two sentences, front-loaded with the main purpose and scope, then provides key constraints (120 months, return contents) and a free note. No fluff, every sentence adds value.

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 conversion tool with no output schema, the description explains what it returns (tipo de cambio o factor, totales, meses sin dato), which is sufficient. It covers the main inputs and limits. It could add a note on error cases (e.g., invalid format) but overall it's complete for an agent to call it correctly.

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 100%, so schema already documents each parameter. The description adds context on the montos format and explains the 'a' enum values, but it largely re-states what the schema provides. For example, the description explains 'ars_hoy' as pesos ajustados por inflación, which is already in the schema, and defaults are in schema too. Thus a baseline 3 is appropriate.

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 clearly states the tool converts Argentine peso amounts across different months to dollars using monthly exchange rates or to today's pesos adjusted by IPC. It specifies the resource (montos in ARS) and the verb (convertir), and clearly distinguishes it from sibling tools like serie_economica or inflacion_entre_fechas which focus on data series or inflation between dates, not amount conversion.

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?

The description specifies the input format (pares AAAA-MM:monto) and the destination options (usd_oficial, usd_blue, etc.), plus the limit of 120 months per call. It implies usage for conversions across months but doesn't explicitly say when NOT to use it or when to prefer siblings like inflacion_entre_fechas for pure inflation series, which would clarify routing.

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