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

The description adds important behavioral context beyond annotations by warning that setting is_default to true displaces the previous default tariff. It also states that the tool returns the created group with its id. While it does not cover authentication, rate limits, or rollback, no annotation contradiction exists and the key side effect is 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?

The description is dense but efficiently organized: main action and return value first, mode-to-price mapping second, and the cautionary side effect last. Every sentence earns its place, and there is no redundant or filler content.

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 tool with 7 parameters and no output schema, the description is complete enough for correct invocation. It covers the purpose, return contract, per-mode parameter selection, the default-tariff side effect, and directs the agent to the relevant listing tool. No critical usage detail appears to be missing.

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?

Although schema coverage is 100%, the description adds decisive value by mapping each billing_mode to its relevant price field and by explaining combined, pvpc_margin, and free behavior. The instruction to fill only the price of the chosen mode prevents invalid combinations. This goes well beyond the schema's enum descriptions.

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 opens with 'Crea un grupo de tarifa y devuelve el grupo creado con su id', stating a clear verb, resource, and return value. It distinguishes the tool from siblings such as askacharge_listar_tarifas and the other crear_* tools by specifying exactly what entity is created.

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?

It gives concrete usage guidance: 'Rellena solo el precio del modo elegido' and enumerates which price parameter belongs to each billing_mode. It also points to askacharge_listar_tarifas for viewing existing tariffs. It lacks an explicit 'when not to use' statement, but the intended use is unambiguous.

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