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

With no annotations the description carries the full burden, but it does disclose two real behavioral traits: the result is 'floored at zero' (negative intrinsic values clamp to 0) and calls are gated by '5 free trial calls per signed wallet,' which signals an auth/pricing precondition. It says nothing about return shape, precision, or error handling, so it is only partially adequate.

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?

A single front-loaded sentence carries the computation, and the trial-call note is appended compactly. Slightly noisy with the emoji and marketing aside, but nothing structurally wasteful.

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?

No annotations, no output schema, 0% schema coverage, and 4 params — the description should therefore be doing more. It omits the 'type' semantics and the spot-vs-price distinction, leaving an agent able to guess but not to call correctly with confidence.

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 the description clarifies only spot and strike. It never explains the 'type' parameter (call vs put, no enum declared) nor resolves the ambiguity between the 'spot' and 'price' parameters, which appear to duplicate each other. With four undocumented params this is a significant gap.

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?

Specific verb+resource: 'Computes call or put intrinsic value from spot and strike prices, floored at zero.' An agent immediately knows this is an options-math calculator. It does not name sibling x402-option-time-value (time value vs intrinsic value) or the black-scholes siblings, so it stops short of 5.

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?

No when-to-use statement, no exclusions, no alternatives. For an agent choosing between intrinsic value and time value, the definition gives no routing signal even though x402-option-time-value exists as a sibling.

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