finance.black_scholes

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

Annotations already cover readOnly/idempotent/closed-world, so the description earns credit for adding what they can't: units for every input (연율 소수, 연 단위), the 12-significant-digit output precision, and the vega/theta conventions ('베가는 변동성 1.0 당 변화량, 세타는 연 단위'). It doesn't touch error handling or sign conventions, which keeps it from a 5.

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 sentences, front-loaded with the purpose and outputs, then input conventions, then scope limits. Dense but every clause carries information; no filler.

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?

An output schema exists, so return values needn't be spelled out; the description instead supplies the conventions an agent needs to call it correctly (units, string type, precision, European-only scope). Only the omission of spot/strike meaning and dividend_yield's default keeps it from 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 coverage is 0% and there are 7 params, so the description carries the burden—and it does: option_type is 'call 또는 put', rate/sigma/dividend_yield are annualized decimals, time_to_expiry is in years, and all inputs are Decimal strings. Spot and strike are left unstated and dividend_yield's default of 0 isn't mentioned, but the critical unit/format semantics are covered.

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 a specific verb and resource ('Black-Scholes 유럽형 옵션의 가격과 델타, 감마, 베가, 세타, 로를 계산한다'), naming exactly which Greeks are returned. This distinguishes it from the payoff-only sibling finance.option_payoff, though no sibling is named explicitly inside the description itself.

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 gives an explicit exclusion: American options and early exercise are out of scope ('미국형 옵션이나 조기행사에는 맞지 않는다'), which tells the agent when not to use it. It doesn't name a preferred alternative for those cases, so it stops just short of full routing guidance.

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