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

Annotations already indicate read-only, idempotent, and non-destructive nature. The description adds useful behavioral details: it is hosted by the platform, requires pre-paid credit per query, no confidential data, and notes LGPD responsibilities for the customer. These go beyond the annotations and inform the agent about cost and legal usage, though it doesn't mention response format or errors.

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 relatively concise, opening with the core purpose in the first sentence, then adding hosting, payment, and legal context. It is structured and not overly verbose, though the LGPD and payment details could be streamlined. Still, each sentence adds value, so it earns a high score.

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?

With 5 parameters, no output schema, and no parameter descriptions, the description is incomplete. It does not indicate what the tool returns (e.g., installment details) or explain the pre-paid credit process beyond a mention. The lack of output expectations and parameter hints makes the tool under-specified for an agent to use correctly.

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 for the 5 parameters, but it provides no parameter-specific guidance. It only gives general domain context (IPTU) without explaining which parameters are required or how they relate to the query. This is a significant gap given the schema has no descriptions, leaving the agent without clarity on what values to supply.

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 is for consulting IPTU installments from Campinas city hall, using 'Prefeitura SP Campinas: Parcelas IPTU, consulta em fonte oficial' which specifies the verb (consulta) and resource (IPTU parcelas). It also distinguishes from sibling tools (which are generic platform tools) by focusing on a specific official data source.

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 that this is for official Brazilian data (particularly IPTU) and mentions payment per query and no platform credentials needed. It implies usage for IPTU lookups but does not explicitly exclude alternative tools; however, siblings are unrelated, so no alternative is needed. It lacks explicit 'when not to use' but has enough context for the intended use case.

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