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

Annotations already declare readOnlyHint=true, so the description correctly doesn't mention mutation. It adds context on data sources (INDEC, mercado), aggregation behavior (promedio de días hábiles o cierre), and the free nature. It could clarify response structure (e.g., time series format), but doesn't contradict 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 comprehensive and efficiently packs a lot of information into a few sentences. It fronts the core purpose and lists series, then covers aggregation and defaults. It's longer than ideal but every sentence serves a purpose; could be split into better structure, but acceptable.

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 read-only data retrieval tool with rich parameter schema (enums and defaults) and no output schema, the description covers all essential calling information: what data is returned, aggregation options, date behavior, and source. No critical gaps for an agent to invoke 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 describes all parameters with descriptions and enums. The description adds value by clarifying aggregation semantics (diaria limited to 10 years, mensual uses average or close) and that 'hasta' defaults to last data point. This goes beyond the schema's minimal descriptions, so it enhances parameter understanding.

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 fetches Argentine economic series between two dates, enumerating the available series (dólar oficial, blue, MEP, CCL, IPC, UVA, etc.). It distinguishes from siblings by focusing on economic data rather than company/person lookups or currency conversion. Includes default behavior without dates.

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 explicitly mentions aggregation options (diaria with 10-year limit, mensual_promedio, mensual_cierre) and default date behavior. While it doesn't name specific siblings as alternatives, it clearly implies usage context for economic queries; the sibling list shows other tools with different purposes. Could be more explicit about when not to use it, but given no overlapping tools, it's sufficient.

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