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

Annotations already declare readOnlyHint: true, idempotentHint: true, and destructiveHint: false, so the safety profile is clear. However, the description adds no additional behavioral context (e.g., data lag, authentication requirements, return format) beyond what annotations provide.

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 a single sentence, which is concise, but it is too short to be considered appropriately sized. It lacks essential details about parameters, output, and usage, making it incomplete.

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?

Given the tool has 3 undocumented parameters and no output schema, the description is grossly inadequate. It fails to explain what each parameter does, what the return value represents, or how the tool behaves. The description is completely insufficient for an agent to use the tool 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?

The input schema has 3 parameters (ap, data, account) with 0% schema description coverage. The description does not explain any of these parameters, leaving their meaning and usage completely unspecified. The description should compensate for the lack of schema descriptions, but it does not.

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 says 'Historical series of portfolio evolution on B3,' which gives a general purpose but is vague and does not differentiate from siblings like b3_get_patrimonio (portfolio) or b3_get_posicao (position). The verb 'get' implies retrieval, but the scope is unclear.

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?

No usage guidelines are provided. There is no indication of when to use this tool over alternatives, no prerequisites, and no context about typical use cases (e.g., historical analysis vs. current snapshot).

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