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

Annotations already declare readOnlyHint=true and idempotentHint=true. The description adds valuable behavioral details: it's hosted by the platform without credentials, requires payment per query, accesses official non-confidential data, and assigns LGPD data-controller responsibility to the client. This goes beyond the annotations without contradicting them.

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 compact and front-loads the purpose ('Certidão Negativa de Débitos, consulta em fonte oficial'). It includes necessary operational and legal context (payment, credentials, LGPD) without excessive verbosity. Each sentence adds meaningful information, though it could be slightly more structured.

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 description covers the tool's purpose, payment, data source, and privacy responsibilities, but lacks details about parameter usage (e.g., which identifier to provide) and expected output or edge cases. Since there is no output schema and the description doesn't clarify return values, completeness is moderate. It is a minimum viable description for a simple lookup tool.

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 schema lists 'cpf' and 'cnpj' as optional strings, but the description gives no guidance on how to use them (e.g., either can be provided, at least one is needed, what they represent beyond being identifiers). Since schema coverage is 0% and no parameter details are given, the agent must infer from names alone, which is insufficient for proper usage.

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 the tool's purpose: 'Prefeitura AP Santana: Certidão Negativa de Débitos, consulta em fonte oficial' — a specific verb (consulta) and resource (CND from a specific prefecture). It is precise and distinct from the generic sibling tools (authenticate, connect, etc.), making it unambiguous.

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 conveys that this is for querying official Brazilian data (CND) and mentions it's read-only without platform credentialsikuha, which clarifies context. However, it doesn't explicitly compare with alternatives or state when not to use it. Given the sibling tools are generic (authenticate, marketplace, etc.), the usage context is sufficiently clear, but no exclusions are provided.

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