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

Annotations indicate readOnlyHint=true, which is consistent with a calculator tool. The description adds that it is free with limited use ('Gratuito (uso limitado)') and explains the computational logic without any contradiction.

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 dense paragraph that front-loads the main purpose and then details parameters. It is not overly verbose, but could benefit from structuring (e.g., bullet points) to improve readability.

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 15 parameters and no output schema, the description covers key inputs and behavior but does not describe the output format. The free/limited use note adds context, but completeness is hindered by missing output information.

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?

Despite 0% schema description coverage, the description adds substantial meaning to many parameters (xr, I_load_A, Fter, Ith_A, Idyn_A, Rct_ohm, etc.), explaining their role in the calculation. Some parameters (e.g., api_key) lack explanation, but the core ones are well-covered.

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?

Clearly states the tool sizes protection CT per standards (IEC 61869-2/NBR 6856) and specifies the goal: smallest primary that avoids saturation. This differentiates it from sibling tools, none of which appear to perform CT sizing.

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 implies when to use certain parameters (e.g., xr for asymmetric fault, Ith_A/Idyn_A for thermal/dynamic limits) but does not explicitly state when to use this tool versus alternatives or when not to use it. No exclusions or sibling comparisons are provided.

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