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

With no annotations at all, the description carries the full burden, and it does disclose the two things an agent most needs: this is a computation over Danish banking rules and each call is metered at 0.005 USD via x402. It is silent on whether the call has side effects, how the date is interpreted (timezone), and error behavior for malformed dates.

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?

A single dense sentence that front-loads the resource and then the four capabilities, followed by the price. Slightly comma-chained, but no sentence is wasted.

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, so the description is the only signal about results — it implies the response covers banking-day status, closure reason, next day, and the shifted date. That is reasonably complete, but without field names or response shape an agent still cannot anticipate the return payload for the `add` path.

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% — both `date` (YYYY-MM-DD) and `add` (0-260 banking days) are documented in the schema. The description only restates the additive behavior as "date + N banking days" and adds the payment-deadline framing, which gives useful intent but no new mechanical detail such as what happens at the 0 and 260 boundaries.

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 a specific resource (Danish banking days) and enumerates the concrete operations: is-it-a-banking-day, closure reason, next banking day, and date + N banking days. An agent knows exactly what it gets. It stops short of 5 because the obvious near-sibling eu_working_days is never referenced, and the tool bundles four outputs into one call without saying whether they are returned together or selected.

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?

"Payment deadlines" implies a use case, so usage is inferable. But there is no statement of when to prefer this over eu_working_days or a plain calendar calculation, and no exclusions or prerequisites are given.

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