compras_indicadores_por_periodo

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

With no annotations provided, the description adds important behavioral context: it identifies the endpoint URL, describes the data source (Open Data), and mentions a 1-hour cache. This helps the agent understand data freshness and scope. The description does not cover pagination limits or data variability beyond the schema.

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 with four sentences, each providing value: tool purpose, endpoint, data type clarification, use case, and caching. The structure is front-loaded with the main action. No unnecessary repetition.

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 existence of an output schema and 100% parameter coverage, the description provides sufficient context: endpoint, data nature, use case, and cache behavior. It is adequate for an agent to select and use the tool correctly, though more detail on pagination or error handling could push completeness higher.

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 has 100% coverage with descriptions for all four parameters. The description adds context ("ano/mês") and clarifies that omitting month aggregates the year, but this is not significantly beyond the schema. Baseline 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 specifies the tool returns operational metrics of the API (usage metrics like requests, latency, downloads) by period (year/month), distinguishing it from related sibling tools that focus on procurement data. The verb "Retorna" and resource "métricas operacionais" are clear, but the tool name suggests procurement indicators, causing slight ambiguity.

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 explicitly states what the tool does not return ("não dados de compras") and provides a usage context ("análise temporal de disponibilidade do upstream"). However, it does not discuss when to use it versus siblings like compras_indicadores_consolidados or alternatives, missing explicit exclusions.

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