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

Annotations already declare readOnlyHint=true, idempotentHint=true and openWorldHint=false, so the safety profile is covered. The description adds value by enumerating the four returned quantities with their units, which matters because there is no output schema. It does not disclose the underlying formulas or assumptions (e.g. that U defaults to 400 V and results are derived per-phase/three-phase), leaving a small gap.

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 sentences, front-loaded with the computation and followed by a compact result list with units. The second sentence partly restates the first, but the unit annotations earn their place given no output schema.

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 zero required parameters, full schema coverage and read-only annotations, the description supplies what is missing: the exact output quantities and units. Only the calculation assumptions (power factor and efficiency treatment, breaker selection rule) remain undocumented.

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%, with units, ranges and defaults documented for all five parameters, including the DE/CH region enum. The description adds nothing beyond the schema about parameter meaning or interaction (e.g. how η and cos φ feed the calculation), so the baseline 3 applies.

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 states a concrete verb and a precise set of computed outputs: Wirkleistung P_auf [kW], Scheinleistung S [kVA], Leiterstrom I [A] and the IEC 60898 breaker rating for a 400 V three-phase system. That is far more specific than the title alone. Sibling differentiation is impossible because the siblings are opaque IDs (bot_009…bot_065), so full marks on that axis cannot be earned.

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 domain (three-phase motor/supply sizing at 400 V) implies when the tool applies, but the description never states when to use it versus alternatives, nor any prerequisites such as needing the shaft output power or efficiency. Usage is left to inference from the title and parameter names.

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