Listar clases de factura

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

The readOnlyHint annotation already establishes this is a safe read. The description adds that the result is a catalog of valid values to be plugged into a specific field, but says nothing about output shape, whether values are static/cacheable, or whether either tipo returns a different set — modest added value beyond 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?

Two short sentences with zero filler; the purpose is front-loaded and the prerequisite note follows. Every clause carries 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 single-parameter lookup with no output schema and a readOnly annotation, the definition covers what an agent needs to select and call it. A brief note on what the response contains (e.g., identifiers plus labels) would close the only remaining 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?

Schema description coverage is 0%, so the description must compensate, and it partially does by mapping the concept to 'facturas recibidas o emitidas', which corresponds to the received/issued enum. However, it never states that tipo selects between those two sets, nor what each returns, so the enum values are left to be inferred from the schema alone.

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?

States a specific verb and resource ('Lista las clases ... válidas para facturas') and clarifies the domain meaning of 'clases' as expense/income types, which is not obvious from the name. It is clearly differentiated from siblings like cs_list_payment_methods and cs_list_periods by resource, though it doesn't name them explicitly.

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?

Gives an explicit when-to-use signal: 'Necesario para invoiceClass al crear', telling the agent this lookup is a prerequisite for invoice creation. It stops short of naming the consuming sibling (cs_create_received_invoice) or stating exclusions, so it is clear context rather than a full routing rule.

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