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

With no annotations, the description carries the full burden. It discloses the tool's outputs (max loan, car price, rule check) but does not explain how trade-in value factors in or what the 15%-of-income rule check entails. Read-only behavior is implied but not explicit, leaving some ambiguity.

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 a single, well-structured sentence with no wasted words. It front-loads the purpose and quickly enumerates inputs and outputs, making it easy to scan.

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 6 parameters, no output schema, and no annotations, the description is relatively sparse. It does not specify the output format, the exact mechanics of the 15% rule, or the role of tradeIn. While it covers the core purpose, an agent would need additional reasoning to handle all parameters and interpret the result correctly.

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%, so the description must compensate. It maps monthlyPayment, annualRatePct, termMonths, and downPayment to plain-language equivalents and hints at income via the 15% rule. However, tradeIn is omitted entirely, meaning one parameter's semantics remain unexplained.

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 uses a clear verb ('see') and specifies the resource ('max loan and car price'), which distinguishes it from sibling tools like car_loan_calculator. The mention of a 15%-of-income rule check adds unique functionality, making the purpose unmistakable.

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 clearly states the use case ('How much car can you afford?') and enumerates key inputs, giving the agent a sense of when to use it. However, it does not explicitly name alternatives or provide exclusion criteria, so it lacks full guidance.

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