ptax_data

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses that the tool returns both buy and sell rates and that it is only available on business days. However, it does not specify error behavior for non-business days, response format, or other operational details, leaving gaps for an agent.

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 concise, consisting of two sentences with no redundant content. The main action is front-loaded, and the second sentence adds context about PTAX and a key constraint. Every sentence earns its place.

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 query tool with an output schema and well-documented parameters, the description covers the core purpose, the data provided (buy/sell), and the business-day restriction. It could mention error handling or response specifics, but given the tool's simplicity and existing schema, it is reasonably 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 100%, meaning both parameters (data and moeda) are already documented in the schema. The tool description only restates that it uses a date and currency, adding no extra semantic detail beyond the schema, so a baseline score of 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's function: querying the official PTAX quotation (buy and sell) from the Central Bank of Brazil for a specific date and currency. It also explains what PTAX is, distinguishing it from other financial or tax tools among the siblings, making the purpose unambiguous.

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 implies when to use this tool (whenever PTAX rates are needed) but does not explicitly mention alternatives or exclusions. It does note that the tool is only available on business days, which is a usage condition, but lacks guidance on when not to use it or when to prefer a different tool.

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