taxa_selic

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

The description is transparent about the data source (BCB/SGS series 11) and the expected output (list of daily points with rate). It does not mention auth, rate limits, or side effects, but since this is a read-only query tool, the provided information is reasonably complete given there are no annotations to lean on.

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, uses a single clear sentence for the main function, and adds a brief use-case sentence. No fluff or redundancy, and the structure is logical.

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?

The description provides all essential context: data source, period parameterization, output format, and target use cases. Combined with the complete parameter schema, it gives a sufficiently complete picture for correct usage.

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 descriptions already cover both parameters (data_inicio and data_fim) with inclusive date semantics and default behavior, giving 100% coverage. The tool description adds no extra detail beyond what is in the schema, so the baseline 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 that the tool queries the effective daily Selic rate from the Central Bank of Brazil for a specified period, and indicates the output is a list of daily rates. It also lists use cases (interest calculations, monetary correction, policy analysis), making the purpose unambiguous and differentiated from related financial data tools.

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 provides usage context by mentioning usefulness for interest calculations, monetary correction, and monetary policy analysis. However, it does not explicitly contrast with sibling tools like ipca_periodo or ptax_data, so the guidance stops short of a clear when-not-to-use directive.

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