Download Invoice XML

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

Annotations already declare the safety profile (readOnly, idempotent, non-destructive), so the bar is lower. The description still adds useful context: the payload is base64, it is a system-generated Estonian e-arve document, and it is suited for exchange/archival. It omits return size, auth, or rate-limit details, so not a full 5.

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 tight sentences with zero filler; the download purpose and base64 payload are front-loaded, followed immediately by the sibling disambiguation. Every clause earns its place.

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 download tool with no output schema, the description conveys the return format (base64 XML) and the document's nature, and disambiguates from the closest sibling. Nothing essential to correct invocation is missing.

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?

There is a single parameter with 100% schema description coverage, so the schema fully documents 'id'. The description adds no syntax or format guidance beyond what the schema provides, matching the baseline of 3 when the schema does the heavy lifting.

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 (Download) and resource (system-generated e-invoice XML for a sales invoice), and explicitly names the sibling it is not — get_sale_invoice_document — clarifying the format distinction (machine-readable XML vs human-readable PDF). An agent can select it correctly without opening any schema.

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?

It gives clear context for use (e-invoice exchange/archival) and routes the agent to the alternative for human-readable output. It stops short of explicit when-not/exclusion phrasing, but the XML-vs-PDF split effectively signals the choice condition.

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