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

With no annotations provided, the description carries the full burden of behavioral disclosure. It reveals the return encoding (base64 PDF), optional attachment behavior, the exact content of the report, and even a tariff restriction. It does not explicitly state absence of side effects, but for a report-generation tool the disclosed details are strong.

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 and well-structured: it opens with the core purpose, then lists report contents, optional attachment, return format, and tariff requirement. Every sentence carries useful information with no filler or repetition.

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?

Without an output schema or annotations, the description compensates well by detailing report contents, output encoding, and optional attachment. It does not mention error conditions or prerequisites beyond the tariff note, but for a PDF-generation tool the description is largely sufficient.

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 100%, so all five parameters already have descriptions and enums. The tool description reinforces attach_source and file_type semantics but adds no new parameter-level information 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 states a specific verb and resource: it generates a validation report as a PDF/A-3b from an e-invoice. It also names concrete report contents and the base64 return format. However, it does not explicitly distinguish itself from the sibling tool validate_invoice, so the differentiation is only implicit.

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 clear context ('zum Ablegen und Weitergeben' and 'auf Wunsch wird die Rechnung angehängt') implying this tool is for producing an archival report after validation. But it gives no explicit when-to-use vs. alternatives such as validate_invoice or check_consistency, leaving the selection to inference.

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