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

Annotations declare readOnlyHint=true and idempotentHint=true, which the description complements by disclosing payment requirements (prepaid credit), legal responsibilities (LGPD), and data nature (public, not confidential). This adds value beyond annotations without contradiction, though it does not describe the return format or pagination.

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 concise, covering purpose, payment, data nature, and legal responsibility in four sentences. It is front-loaded with the core purpose, and every sentence adds meaningful context, though the legal and payment details could be more compact.

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 7 parameters, no output schema, and no parameter descriptions in the schema or description, the tool is under-specified. The description provides external context (payment, legal) but fails to explain how to construct a valid query, what the parameters mean, or what the response contains. For a tool with this complexity, it is not complete enough 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%, and the description does not explain any of the 7 parameters (esfera, ente, poder, orgao, exercicio, uf, titulo). The parameter names are somewhat self-explanatory (e.g., 'exercicio' as fiscal year), but the description fails to compensate for the complete lack of schema descriptions, leaving users to guess the meaning of required fields.

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 purpose: 'consulta em fonte oficial' (query from official source) of 'Declaração Fiscal' (tax declaration) from SICONFI. It identifies a specific verb (consultar) and resource (SICONFI fiscal declaration), which distinguishes it from sibling tools that are unrelated (authenticate, connect, etc.).

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 for usage: hosted by the platform, no platform credentials needed, pay per query with prepaid credit, and data is public (not confidential). It implies when to use (to consult official Brazilian fiscal data) but does not explicitly state when not to use or mention alternatives, though none exist among siblings.

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