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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is known. The description adds valuable context: payment requirement (pre-paid credit), data source (official Brazilian sources), and privacy responsibility (client as controller). It reveals that the tool incurs cost, which is not in annotations, and clarifies the data is not confidential.

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, each sentence adds meaningful information: the first states the core function and source, the second covers operational and legal aspects. It is appropriately sized and front-loaded with the purpose. No redundancy or filler.

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?

While the annotations cover read-only and idempotent behavior, the description does not explain what the tool returns (no output schema exists) or how parameters should be provided. It also omits any note about parameter requirements (e.g., needing at least one of CPF/CNPJ) and does not detail post-consultation steps. The tool is moderately simple, but the lack of parameter and output information leaves significant gaps.

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 0% and the description does not mention the parameters (cpf, cnpj_raiz) at all. With no explanation of what these fields represent or their usage (e.g., either CPF or CNPJ root), the agent has no guidance on how to populate them. The description completely fails to compensate for the sparse schema.

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 it consults the CEAT certificate for TRT2, mentioning specific verb ('consulta') and resource ('Certidão Eletrônica de Ações Trabalhistas'). It distinguishes itself from generic platform siblings (authenticate, connect, etc.) by focusing on a specific tribunal and document type.

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 provides clear context about the tool's purpose (official source, citizen-accessible data) and operational constraints (pre-paid credit, LGPD compliance). It does not explicitly state when to use it versus alternatives, but no similar consultation tools exist among siblings, so exclusions are implicit.

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