ipca_periodo

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

No annotations are provided, so the description bears the full burden of disclosing behavioral traits. It only states the return value (monthly percentage variation) but does not mention whether the tool is read-only, if it requires authentication, or any rate limits. For a tool that fetches external data, this is insufficient transparency.

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 that immediately convey the tool's purpose and usage context. Every sentence provides essential information without redundancy.

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 tool is straightforward (date-range query with two parameters) and has an output schema, so the description does not need to detail return values. It covers the core functionality adequately. However, it could mention that the data comes from BCB/SGS series 433, which is already in the description. Small omissions like error handling or data freshness are acceptable given the presence of an output schema.

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%, with both parameters described in the schema itself (e.g., 'inclusive' dates, format). The description does not add additional semantic meaning beyond the schema; it merely restates the purpose. Thus, it meets the baseline without adding extra value.

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 specifies the tool's function: consulting the accumulated monthly IPCA from BCB for a period and returning monthly percentage variation. It uses a specific verb ('Consulta') and resource ('IPCA'), making it distinct from sibling tools that deal with other economic indicators like SELIC or PTAX.

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 that the tool is useful for inflation calculations and monetary correction, which implies appropriate use cases. However, it does not explicitly state when not to use it or provide alternatives (e.g., 'taxa_selic' for interest rates, 'ptax_data' for exchange rates), leaving the agent without clear differentiation guidance.

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