finance_tvm

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

No annotations are provided, so the description carries the behavioral burden. It discloses sign conventions ('outflow negative / inflow positive'), defaults (P_Y=1, C_Y=P_Y, begin=False), and the fact that I is an annual percentage, which are non-obvious behavioral details. It does not mention error handling or exact return shape, but the core behavior is well covered.

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, using a 'When' clause to immediately orient the agent. Each sentence adds distinct value—purpose, parameters, sign convention, defaults, and an example—without any repetition or fluff.

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 tool's nine parameters and lack of annotations, the description covers the main behavioral rules, defaults, and sign convention, while the output schema handles return values. It could be more complete by specifying invalid-input behavior or edge cases, but it is sufficient for routine TVM problems.

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?

With 0% schema description coverage for 9 parameters, the description fully compensates by naming every relevant parameter and adding meaning: solve_for allowed values, 'provide the other four', annual I, payment/compounding frequencies, and begin flag. The example further maps variables to concrete values, making the parameters actionable.

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 opens with 'When: time-value-of-money (loan/annuity) — solve one of N,I,PV,PMT,FV', clearly identifying the domain and the action. This differentiates it from sibling math tools by naming its unique TVM variables and purpose.

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 explicitly states the intended use case ('When: time-value-of-money') and gives concrete invocation guidance: 'solve one of... provide the other four'. It does not name sibling alternatives or exclusions, but the context is clear enough for tool selection.

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