Get Invoice E-Invoice XML

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

Annotations already declare readOnlyHint, destructiveHint, idempotentHint, and openWorldHint. The description adds useful behavioral context: it is a download operation (read-only), only available post-save/send, and returns auto-detected XML formats. No contradictions with 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 concise: two English sentences plus Spanish translation. Every sentence adds value (action, format, precondition). It is front-loaded with the core purpose.

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 simple tool with a single parameter and an output schema (not needing return value explanation), the description is complete: it specifies what it does, what it returns (EN16931 XML formats), and a precondition. No gaps.

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 schema has 100% coverage with a clear description for the single parameter 'id' ('Invoice ID / ID de la factura'). The description adds no further semantics beyond what the schema provides, meeting the baseline.

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 'Download the e-invoice XML for an invoice.' It uses a specific verb and resource, and by specifying the format (EN16931-compliant, auto-detected formats), it distinguishes this tool from siblings like get_invoice (JSON) and get_invoice_pdf (PDF).

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 precondition: 'Only available after the invoice has been saved/sent.' This guides the agent on when to use the tool. However, it does not explicitly mention when not to use it or provide alternatives, though the sibling context implies alternatives exist.

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