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

The description adds rich behavioral context beyond annotations: automatic synonym expansion, ranking by value, default 30-day window, default values (apenas_abertas=true), and item structure (id+valor). No contradiction with readOnlyHint=true or idempotentHint=true—the operation is purely a query.

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 dense and front-loaded, starting with the core purpose. While it uses ALL CAPS for emphasis, which could be seen as shouting, every sentence provides actionable information. It's compact for the amount of guidance offered.

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 15-parameter tool with no output schema, the description covers critical defaults, alternatives, and list of modalities. It explains the return structure minimally (id+valor) and directs to sibling tools for detailed data. Gaps like pagination or handling of 'cnpj' are not addressed, but the description is sufficiently complete for typical use.

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?

With 0% schema coverage, the description compensates by explaining key parameters (termos[], valor_min/max, uf, modalidade, incluir_valor, expandir, apenas_abertas) and the enum values for modalidade. However, not all 15 params are covered (e.g., cnpj, pagina, tamanho_pagina), leaving some room for ambiguity.

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 'Busca PRINCIPAL de licitações abertas' with specific filters (keyword, value range, state, modality, period). It also distinguishes itself from siblings by labeling itself as the main search and referencing specialized tools (pncp_processo/pncp_texto) for other use cases.

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?

Explicitly explains when to use this tool vs alternatives: 'pra itens/preços e leitura do edital use pncp_processo/pncp_texto.' It also provides parameter-specific usage (e.g., 'Passe incluir_valor:false pra uma lista rápida sem valor') and default behaviors, making it clear when to invoke it.

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