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

Annotations already indicate readOnly and idempotent hints. The description adds value by revealing the classification logic (Minijob/Midijob/regular), use of year-specific thresholds and Faktor F, and the employee/employer split—without contradicting the annotations. It does not go into every nuance (e.g., age/child effects), but those are visible in the schema, so no contradiction or major omission.

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 a single dense sentence that packs the subject, scope, core actions, and legal reference without fluff. Every phrase contributes: the tool name is not merely restated, and the sentence front-loads the key concept 'Midijob/Uebergangsbereich' before detailing computation. This is concise and well-structured.

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?

For a complex German payroll tool with 7 params and an output schema, the description is complete enough: it explains the classification and computation behaviors, and the schema covers parameter meanings and return structure. It does not explicitly mention edge cases (e.g., age-related surcharge) but those are in the schema. Slightly less than perfect because it could briefly note that results depend on optional parameters, but core context is present.

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 does not add detailed parameter-specific semantics beyond mentioning 'year's rates' and 'Faktor F'; individual params like age, children, bundesland are only explained in the schema. Thus, it neither hurts nor significantly improves parameter understanding beyond the structured schema.

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 clearly states a specific verb+resource: it classifies monthly pay as Minijob/Midijob/regular and computes contribution bases and splits. It references the legal basis (§20 Abs. 2a SGB IV) and explicitly covers 2023-2026, distinguishing it from generic calculators like 'contributions' or 'de-net-salary'.

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 gives clear context: it is for German Midijob/Uebergangsbereich calculations for 2023-2026, including classification against thresholds and computing Faktor F. It implies when to use it (when pay falls in the transition band) but does not explicitly name alternatives or exclusions among sibling tools. This matches 'clear context, no exclusions'.

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