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

Annotations only say it is a non-read-only, idempotent, open-world call; the description goes well beyond that by disclosing the async contract (returns immediately, must poll), the exact quota model (2 full scans per calendar month per credential, shared per-IP monthly budget for anonymous callers), and a hard refusal condition for existing products. These are precisely the operational facts an agent needs before spending a limited scan budget.

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?

Four sentences, each load-bearing: action and async behavior first, then quota, then the polling follow-up, then the refusal case. No restatement of the tool name or filler, and the ordering front-loads the things an agent must know before calling.

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?

There is no output schema, and the description compensates by explaining that this call yields no report at all and that results come from polling get_site_report. With one fully documented parameter and annotations covering the safety profile, nothing material is missing for correct invocation.

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 coverage is 100% for the single 'domain' parameter, so the baseline would be 3; the description earns one more by adding a constraint the schema does not express — that domains already registered as krawlup products are rejected. It does not add format or normalization details beyond the schema's example.

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?

States a specific verb and resource — 'Start the free public scan for any website' — and immediately clarifies that it returns asynchronously rather than delivering results. This cleanly separates it from the sibling get_site_report (which fetches the result) and from trigger_rescan (which targets already-tracked products).

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?

Gives explicit next-step guidance ('Poll get_site_report for the domain until scanStage clears') and an explicit exclusion (domains already listed as krawlup products are refused, use the dashboard instead). The one gap is that trigger_rescan is never named, so an agent can't tell from this description which of the two scan-starting tools to use for a product it already owns.

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