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

readOnlyHint already covers the safety profile, and the description goes beyond it by disclosing what is returned ('no answers') and warning that euro values in answers are SSOT tokens rather than a live invoice — a meaningful data-semantics caveat. It stops short of describing ordering or pagination.

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?

Three short, front-loaded clauses with no filler; the WHAT/scope/routing order is sensible. Uppercase labels and arrow notation are terse but not wasteful, and the SSOT disclaimer earns its place as scope clarification.

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?

With an output schema present, return values need no prose, and the description covers content scope, the no-answers caveat, and the sibling alternative. Only the absence of any 'when to use this list' signal keeps it from being fully complete.

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 single locale parameter is documented exhaustively in the schema (100% coverage, enum with defaults and URL-prefix semantics), so the schema carries the burden. The description adds nothing about locale, which is acceptable but yields only 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 'WHAT' clause states the specific resource (FAQ question list) and the exact payload shape ('id + question, no answers'), which sharply distinguishes it from the answer-returning get_faq sibling. It is clear and concrete, though the framing is telegraphic rather than a clean sentence.

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 routes the agent explicitly to get_faq({id}) or get_faq({q}) for fetching individual FAQs, and names the correct chain (get_prices.composition → get_ort_datetime → get_invoice_line_items) for customer totals. It does not state when to prefer this list over other list_* tools, so a small gap remains.

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