calculate_futures_price

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

With no annotations, the description carries full burden. It discloses the model (cost-of-carry), formula, and use of dividend_yield. It does not cover assumptions or limitations, but it is transparent enough for an agent to understand the behavior.

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, front-loaded with the purpose, and every sentence adds value. No wasted words.

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 financial complexity and the presence of an output schema, the description adequately covers the formula, usage context, and key parameters. It could mention edge cases but is sufficient for most agents.

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%, so description must compensate. It mentions spot_price, annual_rate, years, compounding (default continuous), and dividend_yield, with explanation that dividend_yield is for stocks/indices. The formula ties parameters together, adding significant meaning beyond the schema.

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 states the tool calculates the fair value of a futures/forward contract using cost-of-carry, which is a specific verb-resource combination. It distinguishes itself from sibling tools like 'calculate_futures_hedge' by focusing on pricing.

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 says 'Use when a user asks what should the futures/forward price be, about carry, contango/backwardation, or arbitrage-free pricing...' This provides clear context for usage, though it does not explicitly mention when to avoid using it.

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