Create Invoice

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

Annotations indicate a mutation tool (readOnlyHint=false). The description adds significant behavioral context: auto-generated invoice number, default draft status, today's date, and support for advanced features like IRPF, equivalence surcharge, series, prepayment, and global discount. This goes beyond what annotations provide.

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 concise, front-loaded with essential information, and includes a helpful example. The bilingual content (English and Spanish) adds redundancy but is not excessive. Every sentence contributes meaningful guidance.

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?

Given the tool's complexity (19 parameters, 3 enums, output schema present), the description covers core behavior, prerequisites, defaults, and advanced features. It does not need to explain return values due to the output schema. The context is sufficient for an agent to invoke the tool correctly.

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 coverage is 100%, so baseline is 3. The description adds value by providing an example that demonstrates how to use common parameters (clientName, items, taxRate, irpfRate) and highlights advanced features (IRPF, surcharge, series, prepayment, discount) that correspond to schema properties.

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 states 'Create a new invoice' and specifies required parameters (client name, at least one line item). It distinctively identifies the creation action compared to sibling tools like get_invoice, update_invoice, and delete_invoice.

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 explicitly states prerequisites (client name, at least one line item) and defaults (auto-generated number, draft status, today's date). It provides an example but does not explicitly state when not to use or mention alternatives, though none are directly relevant.

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