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

No annotations are provided, so the description carries the full burden. It discloses data-source behavior (DFP annual vs ITR quarterly granularity with overlapping history), scope limitations (stocks only; FII not supported in this format), and authentication requirements (chave_api needed except for WEGE3). It does not cover error behavior, invalid-key handling, or output structure, but the core behavioral traits an agent needs are disclosed.

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?

Three compact paragraphs, each with a distinct job: core functionality and granularity, scope/exclusion with sibling routing, and access requirements. The key purpose is front-loaded and every sentence carries information — no filler or repetition of schema fields.

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 3-parameter tool with no annotations and no output schema, the description covers what data is returned, source traceability, granularity semantics, scope restrictions, and authentication conditions. Minor gaps remain — exact return format and error behavior — but nothing that would prevent correct selection and invocation.

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 schema. It fully explains `trimestral` with the concrete outcome of each value (annual DFP vs isolated ITR Q1-Q3) and explains when `chave_api` is required (all tickers except WEGE3). `ticker` is only implied as a stock code rather than explicitly described, so the compensation is strong but not complete.

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 identifies a specific resource and output: standardized accounting accounts for a stock (receita, EBIT, lucro, PL, dívida, caixa) with the originating CVM account for each figure, making the data auditable end-to-end. It also distinguishes itself from siblings by stating 'Só ações' and explicitly routing FII queries to the `fii` tool. The verb is implied rather than explicit ('returns/provides'), but the intent is 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?

Gives explicit when-to-use guidance: stocks only, with FII explicitly excluded and routed to the sibling `fii` tool ('o que existe é o informe mensal, exposto por `fii`'). It also explains the `trimestral` choice as a granularity decision (False → annual DFP, True → ITR Q1-Q3, both covering the same history) and the access condition (WEGE3 free, others require chave_api). Nothing is left to inference.

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