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

No annotations were provided, so the description carries the full burden of behavioral disclosure. It excels here: it transparently reveals the calculation behavior, including specific rates (2.7% Zoll, 19% MwSt), currency conversion logic (USD×Kurs), and the fact that modell_id fetches a documented list price. However, it doesn't address edge cases such as what happens when both parameters are provided simultaneously or what error/fallback behavior occurs for invalid inputs.

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?

Two well-structured sentences that front-load the core purpose and formula. Every element serves a purpose: the formula, the parameter choice, and the use case. Slight redundancy exists due to the bilingual structure (German and English essentially repeat the same information), but both versions are concise and add accessibility value for the target audience.

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 pure calculation tool with no output schema and no side effects, this description is nearly complete: it covers purpose, formula, parameter selection, and geographic context. The version_eur default (250/800/1500€ by weight class) is mentioned in the schema as required. The only gap is the missing description of the return format (total amount only vs. detailed breakdown), but that is acceptable given the absence of an output schema.

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%, so the baseline is 3. The description adds meaningful value beyond the schema: it establishes the mutual exclusivity relationship between modell_id and preis_usd (not clear from the schema alone) and ties the parameters into the overall cost formula context. It also references the weight-class-based default for versand_eur, which enriches understanding of that 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 uses a highly specific verb ('Rechnet'/'calculating') paired with a precise resource ('Import-Faustregel für den Direktimport eines Roboters'). It includes the exact formula (Warenwert + Versand + 2.7% Zoll + 19% Einfuhrumsatzsteuer), making it impossible to confuse with any sibling. It clearly distinguishes itself from compare_robots, search_robots, etc., which are about comparison and search, not cost calculation.

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 explicitly explains the either/or choice between modell_id and preis_usd ('Entweder modell_id... oder preis_usd frei angeben'), providing clear guidance on parameter selection. It clearly defines the use case (direct import from China/USA). However, it lacks explicit exclusion criteria or named alternatives (e.g., 'for trade pricing, use X').

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