Compare filing jointly vs separately for student loans

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

With no annotations provided, the description must carry the full burden and does so excellently. It clearly warns that the tool models only the loan side, omits tax costs that can reverse the answer, and explicitly states that this limitation appears in the tool's output. It also discloses the output is a side-by-side comparison with monthly and lifetime differences.

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 four sentences long and front-loaded with the core purpose. Every sentence earns its place: the scenario and outcomes, the return summary, the essential tax caveat, and an explicit usage rule. There is no filler or redundancy.

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?

For a six-parameter calculator with no output schema, the description provides the necessary decision context: married/IDR eligibility, the two filing statuses, the monthly and lifetime outputs, and a built-in disclaimer. However, it does not specify the exact output shape or assumptions about which IDR plan applies, leaving minor gaps.

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?

The schema descriptions already cover 100% of parameters with detailed entries, so the baseline is 3. The tool description adds general context by explaining the role of spouse income in the filing decision, which slightly reinforces the meaning of spouseAgi, but it does not add unique meaning for balance, ratePct, loanType, or dependents.

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 the specific verb 'prices' and clearly identifies the resource: the married filing-jointly vs separately decision under an income-driven federal student loan plan. It explains the comparison and result (monthly and lifetime cost difference), and the context distinguishes it from the sibling tools that focus on plan choice or RAP payment estimation.

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 explicit context for when to use this tool ('For a MARRIED borrower on an income-driven federal student loan plan') and directs the agent to 'Use it whenever a married borrower asks about IDR, RAP, PSLF or how to file.' It does not name alternative tools or provide a when-not-to-use statement, and the broad 'asks about IDR' phrase could invite overuse, so it is strong but not top-scoring.

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