Black-Scholes option calculator

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

Annotations already declare readOnly, idempotent, closed-world, and 'Works offline' corroborates openWorldHint=false. The description adds genuine behavioral value the annotations lack: it discloses the output contents (which Greeks, theta normalized per day) and that the tool also performs IV back-solving, which is a distinct execution path.

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?

Two sentences, zero filler, and the primary capability plus its output list is front-loaded ahead of the alternative IV-solving mode. Every clause carries 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?

With no output schema, the description correctly enumerates the return values and notes the theta-per-day convention. It does not cover edge behavior — e.g. what happens when neither volatility_pct nor market_price is supplied — which would be useful for an agent deciding which optional inputs to pass.

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 spot, strike, rate_pct, option_type, market_price, days_to_expiry, volatility_pct and dividend_yield_pct. The description only re-emphasizes the market_price/IV relationship the schema already states, adding little beyond the baseline.

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?

States a specific verb ('Price') and resource ('a European option'), then enumerates exactly what is returned (delta, gamma, theta per day, vega, rho, probability ITM). 'Works offline' cleanly separates this pure calculator from every sibling, all of which fetch market data (get_option_chain, get_quote, etc.).

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 'or give market_price to back out implied volatility' clause clearly defines the second invocation mode, and 'Works offline' implies this is the tool to use when you need computed values rather than a data lookup. It stops short of naming a sibling (e.g. get_option_chain) as the alternative for live quotes, so there is no explicit when-not guidance.

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