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

No annotations exist, so the description carries the full burden; it does disclose the meaningful behavioral constraint that only ACTIVE operadoras are searched, which the schema does not. It says nothing about result ordering, pagination behavior, or what happens when no match is found, leaving the read semantics partly implicit.

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?

Three compact sentences with zero filler: what it searches, when to use it, when to use a sibling instead. The core verb and resource are front-loaded, and the warning against misuse comes before any caveat.

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?

An output schema exists, so return values need not be described, and the description adequately covers search semantics and sibling routing for a two-parameter read tool. The only shortfall is the undocumented 'limite' result-cap parameter, which affects how many hits an agent should expect.

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 0%, so the description must compensate: it usefully explains that 'texto' is a multi-field query key accepting name, registro, CNPJ or locality. It never mentions the 'limite' parameter, its default of 10 or its maximum of 50, so half the parameters remain undocumented in prose.

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?

States a specific verb and resource ('Busca operadoras ativas') plus the searchable fields (nome, registro, CNPJ, localidade), so the agent knows exactly what the tool returns. It names tiss_rede as the wrong tool for hospital links, but does not distinguish itself from the closely named siblings operadora_perfil and operadora_rede.

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?

Explicit 'Quando usar' (locate an operadora in the public base) and 'Quando não usar' (hospital links → use tiss_rede) sections give real routing guidance rather than implied usage. The gap is that operadora_perfil and operadora_rede, which sound almost identical, are never mentioned.

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