Download Invoice File

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

Annotations declare readOnlyHint, idempotentHint, and non-destructive. The description adds that the API returns whatever representation it can render, which clarifies behavior beyond annotations. No contradiction.

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 sentences, no wasted words. Every clause adds value: verb+resource, default behavior, optional parameter, caveat on API behavior.

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 simple parameters (2, one optional) and no output schema, the description adequately covers what the tool does and what to expect. Annotations confirm safety. No missing critical information.

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 provides full parameter descriptions (100% coverage). The description adds context beyond schema: default to PDF, XML for XRechnung, and that the API returns whatever it can render. This helps the agent understand the behavior of the format parameter.

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 the action (download) and resource (invoice file). It specifies the default format (PDF) and an alternative format (XML). Among many sibling download tools, the name and description uniquely identify this tool for invoice files.

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 implies usage for downloading invoice files. It doesn't explicitly list alternatives, but the tool name and context among sibling download tools make the purpose clear. The added note about format="xml" provides guidance on optional usage.

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