12 mayores accionistas

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the period scoping ('para un período') but does not explain the cryptic 'pestanías 5/21' or any additional behavioral details like output characteristics or data source.

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 concise sentence that conveys the core purpose without redundancy. However, the phrase '(pestanías 5/21)' is cryptic and likely a typo for 'pestañas', which detracts slightly from clarity.

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 an output schema present, return-value documentation is unnecessary, but the description leaves significant gaps: it does not explain the parameters, the meaning of 'pestanías 5/21', or how to identify the emisor. For a tool with three parameters and zero schema coverage, this description is incomplete.

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 provides no explanation of the three parameters (mes, rut, anio). The mention of 'período' hints at time-related parameters but does not distinguish mes from anio or explain that rut refers to the issuer. The description completely fails to compensate for the missing schema documentation.

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 identifies the resource: 'Los 12 mayores accionistas de un emisor para un período' (the 12 largest shareholders of an issuer for a period). It differentiates from sibling tools by specifying 'emisor' and the fixed number 12, though lacks an explicit verb like 'obtener' or 'listar'.

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 guidance is provided on when to use this tool vs alternatives. The description merely states what data it returns, with no mention of use cases, exclusions, or related tools such as cmf_api_accionistas_institucion.

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