Calculate German property depreciation

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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is covered. The description adds useful behavioral context beyond that by stating the estimate is 'indicative' and 'non-binding,' and by disclosing that omitting modernization components 'assumes no modernization and produces the highest possible remaining-useful-life benefit.' This gives the agent meaningful expectation-setting without contradicting the annotations.

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 front-loaded with the primary action and resource, and every sentence earns its place: purpose, usage scope, modernization guidance, and legal disclaimer. It is compact enough for a complex 13-parameter financial calculation tool while avoiding redundancy or filler.

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?

The description covers the core purpose, when to use it, apartment-building handling, an important assumption about missing modernization data, and the non-binding nature of the result. With annotations covering safety and an output schema present, the description is reasonably complete, though it could be stronger by explicitly naming the sibling tool and the situations that would route to it.

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 adds value beyond the schema by explaining the consequence of omitting the modernization object—it assumes no modernization and affects the remaining-useful-life result. It also gives guidance on how to pass floor-area figures for apartment buildings, which helps the agent reason about propertyType and floorArea semantics.

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 opens with a specific verb and resource: 'Calculate an indicative German real-estate depreciation (AfA) estimate through AfaMax.' This clearly identifies the tool's function and distinguishes it from the sibling calculate_purchase_price_allocation, which targets a different calculation even though the sibling is not named.

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 use context: 'Use this for residential German property' and provides special guidance for apartment buildings. It also instructs the agent to 'Ask for all eight modernization component states whenever possible,' but it does not explicitly state when not to use this tool or mention the alternative sibling, so it stops short of full when/when-not guidance.

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