get_ptax_by_period

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

The description adds meaningful behavioral context by specifying that the series covers business days only and represents the official closing rate from Banco Central do Brasil. With no annotations to cover the safety profile, some gaps remain: it does not mention response shape, date-boundary behavior, or error conditions.

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 a single front-loaded sentence that communicates the resource, source, scope, and period. Every part adds information and there is 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 simple two-parameter date-range fetch with no output schema, the description is nearly complete. It does not spell out the return format, but the concept of an exchange-rate series is self-evident enough that an agent can invoke the tool 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?

The input schema already documents both parameters with names, formats, and regex patterns, giving 100% schema description coverage. The description does not add parameter-level meaning, so the baseline of 3 applies.

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 verb ('Get') and resource ('official closing USD/BRL PTAX exchange rate series'), and pins down its scope with 'for each business day in a date range.' This distinguishes it from the single-date and latest-rate siblings, though it does not name them explicitly.

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 phrase 'for each business day in a date range' gives clear context: use this tool when you need a multi-day series. However, it does not explicitly say when not to use it or point to alternatives like get_ptax_by_date or get_ptax_latest.

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