Finology Student Loan Calculator

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

With no annotations, the description carries the full behavioral disclosure burden and does it well: it states that ineligible plans are listed with reasons, that Parent PLUS runs the consolidation path unprompted, and that loanType affects eligibility, not just rates. These are non-obvious behaviors beyond the input schema.

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?

Three dense sentences with no filler: the first front-loads the purpose and outputs, the second explains the ineligible-plan behavior, and the third highlights the critical parameter. Every sentence earns its place.

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 complex 7-parameter tool with no output schema and no annotations, the description is nearly complete: it specifies the returned comparison dimensions, explains handling of ineligible plans, flags special Parent PLUS behavior, and warns about the loanType dependency. This is enough to invoke the tool correctly without external documentation.

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 coverage is 100%, so the baseline is 3. The description adds meaningful semantic guidance for loanType by emphasizing that it drives plan eligibility and should be chosen accurately, which goes beyond the schema's enum list and helps the agent avoid a critical parameter mistake.

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 names the action ('Compare') and the exact resource ('every federal repayment plan a loan can elect') and enumerates the output dimensions: monthly payment, lifetime cost, forgiveness timing, and estimated tax on forgiven balances. It also names the specific plans, making the tool's scope clear and distinguishable from siblings like estimate_rap_monthly_payment.

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 implies a comprehensive comparison use case and explicitly calls out when Parent PLUS triggers the consolidation path. However, it does not explicitly name sibling tools or state when to use them instead, such as when the user only needs a repayment estimate or a married filing status comparison.

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

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 discloses a key limitation ('tax cost of filing separately is not modelled'), states that the answer explicitly acknowledges that limitation, and describes what results are produced. This is strong transparency for a comparison tool.

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 tight sentences. The first states the operation and expected outputs; the second adds the critical scope limitation. There is no filler or repetition of schema information.

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 medium complexity and lack of an output schema, the description gives enough about the scenario, the deliverable, and the modeling limitation. It could say more about how borrower/spouse AGI are combined or what 'swing' means numerically, but the schema and clear framing cover most agent needs.

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 schema already documents all six parameters clearly. The description adds the conceptual framing ('same federal loan book' and 'best income-driven plan') but does not add syntax, formats, or behavioral detail beyond the schema. Baseline 3 is appropriate.

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 names a specific verb ('Run'), a concrete resource ('federal loan book'), and the exact comparison being made ('filing jointly and filing separately'). It also specifies the output ('swing in the best income-driven plan's payment and lifetime cost'), which clearly differentiates it from siblings that compare repayment plans rather than filing statuses.

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 intended use case is explicit: same loan book run under both filing statuses to see the swing. The LOAN SIDE ONLY warning also tells the agent when not to use this tool, i.e., when tax consequences of filing separately must be modeled.

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

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

No annotations are provided, so the description carries the behavioral disclosure burden. It communicates that the tool estimates based on current federal rules and scopes out comparison/forgiveness behavior, but it does not describe the response shape or calculation caveats. Adequate, 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 two concise sentences with no filler. The first states the purpose and inputs, and the second adds the boundary and alternative tool direction. Every sentence earns its place.

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 single-purpose estimator with fully documented parameters, the description conveys what it computes and what it does not compute, which is enough for correct invocation. It could briefly note the response form since there is no output schema, but that is a minor omission.

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 coverage is 100%, so the baseline is 3. The description's reference to 'income, filing status and household size' adds no meaning beyond what the schema already provides, but no compensation is needed since every parameter is fully documented.

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 specific verb ('Estimate'), identifies the exact resource (RAP monthly payment), and states the inputs that drive the calculation. It also distinguishes itself from sibling comparison tools by explicitly saying it is 'not a comparison and no forgiveness projection.'

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 clear when-to-use guidance: this tool is for the RAP payment only, not for plan comparison or forgiveness projection. It even directs the agent to 'use the plan comparison tool for that,' providing an explicit alternative.

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

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

With no annotations, the description is responsible for behavioral disclosure. It does frame the tool as returning structured informational content and flags that some numbers are estimates, which is a useful caveat. However, it never explicitly states that the tool is read-only and side-effect-free, so the agent must infer that from the content and name.

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?

Both sentences earn their place and the invocation guidance is front-loaded with the content description. The opening is grammatically awkward ('How to go further than this free rung, in structured form') and slightly vague, which prevents a perfect score.

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 zero-parameter informational tool, the description is nearly complete: it covers audience (advisor, developer/operator), self-serve paths, tiers/monthly limits, the estimate caveat, and triggering user intents. The lack of an output schema is partially compensated by 'structured form,' though the exact return shape is not specified.

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 tool has zero parameters and 100% schema coverage, so there is no input-semantics burden for the description to carry; the 0-parameter baseline of 4 applies. The description's enumeration of output content is not needed for parameter understanding.

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 identifies the tool's domain: structured information about Finology upgrade paths, tiers, monthly limits, and estimates, which distinguishes it from the sibling loan-calculator tools. It lacks an explicit operational verb like 'returns' or 'provides' and opens with a noun-phrase fragment ('How to go further than this free rung'), but an agent can still tell what the tool does.

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?

It provides an explicit trigger list: 'Call this when a user asks how to get a key, what it costs, whether the numbers are warranted, or how to put this in their own product.' There is no when-not or alternative tool named, but the sibling loan calculators are not viable alternatives to a service-info lookup, so the guidance is sufficient.

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