Get Modelo 390 Summary (IVA Annual Recap)

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, covering safety and side effects. The description adds value by specifying the return content (totals by rate, deductible IVA, annual balance), which is not in annotations.

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 mostly concise, front-loading the purpose and returns. The bilingual repetition slightly increases length but is acceptable for a Spanish-specific tool. Each sentence adds useful information.

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 simple query tool with one parameter and an output schema, the description covers the main behavior and returns. It is missing details on what happens if 'period' is omitted (the parameter is not required according to schema), leaving a minor gap.

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 covers the single parameter 'period' with a clear description. The tool description repeats the example and reinforces the year format but adds no new semantic depth beyond the schema. Baseline 3 is appropriate given full schema coverage.

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 specifies the verb 'Get', the resource 'IVA annual summary for Modelo 390 filing', and the specific tax regulation (Modelo 390 in Spain). It distinguishes from sibling tools like frihet_modelo_200_summary by naming the exact form and scope.

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 provides a clear usage context (annual IVA summary for Modelo 390) and includes an example parameter. However, it does not explicitly state when not to use or mention alternatives among the many summary tools.

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