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

The description reveals a non-obvious behavioral trait: the order is not immediately fulfilled—the letter only ships after the customer pays the returned link—and instructs the assistant to hand the link to the user for payment. This goes beyond the bare readOnlyHint/destructiveHint annotations and is essential for correct invocation.

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 three sentences, each adding distinct value: the action, the payment-link behavior, and the pre-summarization instruction. It is front-loaded with the main purpose and contains no filler or redundancy.

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?

The tool has 9 parameters, a nested ontvanger object, and no output schema, yet the description captures the key behavioral contract (payment link, deferred sending) and the prerequisite to summarize. It doesn't explain idempotencyKey or the full return payload, but schema covers the parameters and the payment link is explicitly mentioned, leaving only minor 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?

With 78% schema description coverage, the input schema already documents most parameter meanings. The description itself adds little per-parameter detail, but it does reinforce that the order should be summarized before submission, which helps with documentRef and paginas usage. Baseline 3 is appropriate because the schema carries the burden.

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 names the specific action 'Maakt de bestelling aan' (creates the order) and the returned payment link, clearly distinguishing it from sibling tools (document, landen, prijs, status) which handle document creation, country validation, pricing, and status lookup. The verb+resource combination is specific and unambiguous.

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 explicit workflow instructions: summarize what will be sent, provide the payment link to the user, and ask them to pay; it also clarifies that the letter only goes out after payment. While it doesn't name alternative tools, the use case is unmistakable and the guidance is actionable.

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