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

With no annotations, the description carries full burden. It discloses that both front-end and back-end ratios are calculated and compared to thresholds, which is useful. However, it does not explain output format, data interpretation, or how inputs map to the ratios.

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 two concise sentences, front-loaded with the purpose and enriched with threshold context. No unnecessary words or repetition.

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 the simple three-input, no-output-schema calculator, the description covers the core calculation and threshold comparisons. However, it omits parameter definitions, output specifics, and any assumptions, making it adequate but not fully complete.

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 0%, and the description adds no explicit parameter details. While parameter names are intuitive, the description does not clarify the relationship between housingPayment/otherMonthlyDebts and front-end/back-end ratios, nor does it state that figures are monthly.

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 tool 'calculates front-end and back-end debt-to-income ratio', which is a specific verb and resource. It also mentions comparison against specific thresholds (36%, 43% QM, 50%), distinguishing it from other finance calculators.

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 provides clear context for use: to assess debt load relative to common lending thresholds. It does not explicitly list alternative tools or exclusions, but for a calculator with obvious purpose, this context is sufficient.

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