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

With no annotations provided, the description carries the behavioral disclosure burden. It does disclose default-fallback behavior and the computed outputs, but it remains silent on side effects, auth requirements, or the exact return format. That is adequate for a calculator but not rich.

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 compact and front-loaded with the core action, and every clause adds information (outputs, fallback behavior). It loses a point for the awkward 'calculator calculator' repetition and the dense run-on structure.

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?

Given no annotations or output schema, the output list and fallback note are helpful, but the description does not explain how purchaser affects the fixed compensation or what the returned object looks like. It is functional but leaves some context to inference.

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 by stating that the statutory interest rate is base rate plus 8% and by naming the computed output fields, which clarifies how parameters such as baseRate feed into results.

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 specific action ('Run the ... calculator') and enumerates the outputs (statutory interest rate, interest per day, etc.), so an agent can tell what the tool computes. However, it does not distinguish itself from siblings like calculator_describe, and the duplicated 'calculator calculator' wording is slightly sloppy.

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?

There is no guidance on when to choose this tool over the sibling tools, nor any stated prerequisites or exclusion criteria. The only operational hint is that missing inputs fall back to defaults, which is a behavior note, not a usage policy.

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