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 that the tool returns yearly schedules and book value, which is useful output context. However, it says nothing about required input combinations (e.g., units and totalUnits for the units-of-production method) or any calculation assumptions, so it adds only moderate behavioral value.

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 one front-loaded sentence followed by a URL. It is compact and wastes no words. The URL is arguably not essential for tool invocation, but the overall structure is efficient.

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?

With seven parameters, no required fields, no output schema, and a 100%-covered schema, the description gives minimal but sufficient context: it says what is calculated and which methods exist. It does not explain parameter interactions (like when units or totalUnits are needed) or the shape of the returned schedule. This is adequate but leaves clear gaps for a calculator with this many optional inputs.

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 every parameter is already documented in the schema with type, default, range, and description. The description repeats the method names but adds no syntax or format details beyond what the schema provides. The baseline of 3 is appropriate when the schema does the heavy lifting.

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 the resource (depreciation) and the specific outputs (yearly schedules and book value) plus the four supported methods. This makes it distinguishable from all sibling calculators. It does not explicitly name a sibling it is not, but the resource itself is unique enough that an agent can identify it without cross-referencing.

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 names the four calculation methods but gives no guidance on when to use one method over another or when this tool is appropriate versus alternatives. It also provides no prerequisites or exclusions. An agent gets no routing help beyond the obvious 'this is for depreciation'.

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