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

With readOnlyHint, idempotentHint, and destructiveHint already provided, the description carries a lower burden. It adds useful behavioral context: country scope, monthly calculation, the relevant legal rules, and dependency on the collecting agency's state. It does not describe return shape, but the annotations already cover the safety profile.

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 not cleanly structured: it begins with a terse German sentence, includes a truncated legal citation ('§ 28f Abs. English:'), and then repeats the same information in English. The English tail is redundant rather than additive.

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 should at least indicate what the result looks like; it does not. It is still adequate for a simple read-only calculator because it covers purpose, legal basis, country scope, and state dependence, but the missing return-format and `datum` behavior prevent a higher score.

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 description coverage is 100%, so the baseline is 3. The description's reference to 'your collecting agency's state' maps to the `land` parameter and 'je Monat' maps to `jahr`, but it adds little beyond the schema and does not mention the `datum` 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 names a specific verb ('Berechnet') and a precise resource: the monthly due date of German social security contributions and the contribution statement deadline, with legal citations. It does not explicitly differentiate itself from sibling tools, but the specialized legal terms make the purpose 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?

The description clearly frames the use case ('Berechnet je Monat den Fälligkeitstag... und den Termin für den Beitragsnachweis') and restricts applicability to Germany. It does not mention alternative tools or explicitly state when not to use it beyond the country restriction, so it stops short of a 5.

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