taxa_selic

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

With no annotations, the description carries the full burden. It clearly says it returns a list of daily points with date and rate, implying a read-only query. It lacks explicit statements about safety or authorization, but the verb 'consulta' and the output structure provide adequate transparency for a simple data retrieval tool.

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-loads the core purpose, and has no redundant words. Every sentence adds value: the first defines the action, the second describes output and use cases.

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?

Given the presence of an output schema, the description sufficiently covers return structure (daily points with date and rate). The parameter coverage is 100%, and the tool is unique among siblings, so no extra context is needed.

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 coverage is 100%, so the baseline is 3. The description does not add any additional semantics or constraints beyond what the schema provides for the two date parameters. It simply refers to 'período' which is already covered.

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 queries the daily Selic rate from BCB for a period, returns daily points with date and rate, and mentions use cases. It uniquely names the resource and verb, and among siblings it is the only Selic rate tool, so it distinguishes well.

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 mentions usefulness for interest calculations and monetary correction, but does not explicitly clarify when to use this tool versus related tools like 'calcular_correcao_monetaria' or offer exclusions. The guidance is implied but not definitive.

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