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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds real behavioral context beyond that: default page size 20, hard max 50, presence of TotalGeral in the response, and an explicit anti-hallucination instruction to page rather than invent or aggregate.

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?

Front-loaded with purpose and filters, then pagination guidance, all in a few dense sentences with no filler. Every clause carries operational information.

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 read-only filtered-list tool with an output schema, the description covers everything an agent needs to call it correctly: filters, page sizing, and how to interpret TotalGeral for continued paging. No meaningful gap remains.

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 description coverage, the description compensates fully: it defines Tipo's enum-like values (1=NFe, 2=NFCe, 3=Energia/Comunicacao) that the schema lacks, explains CFOP and Termo as filters, and gives Limite's default (20) and max (50) plus Offset's role.

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?

Specific verb+resource: it lists the company's tax rules and enumerates the domains covered (CFOP, CST, ICMS/PIS/COFINS/IPI/IBS/CBS), cleanly separating it from the sibling mutation tools tributacao_criar and tributacao_editar.

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?

Gives an explicit when-to-use ('Use antes de criar nota fiscal pra LLM saber quais tributos aplicar') plus filter conditions (Tipo/CFOP/termo). It does not name the sibling alternatives for maintaining rules, so it stops short of 5.

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