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

No annotations and no output schema, so the description carries the full burden. It discloses the computed outputs and the scope-change report, and adds a pricing/auth note (5 free trial calls per signed wallet), which is genuine behavioral context. However it never states that the tool is a pure read-only computation, nor which CVSS version or vector dialect it accepts, nor what happens on a malformed vector. For a no-annotation tool this is a substantial gap.

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 substantive clause is front-loaded and informative, but the trailing emoji and "5 free trial calls per signed wallet" marketing text dilute a one-sentence definition and consume space that could have documented the vector format.

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 usefully enumerates the returned values (base score, impact, exploitability, scope changed). But for a 2-parameter, undocumented, unannotated tool it omits the CVSS version, accepted vector syntax, and error behavior, leaving real holes an agent would hit on first call.

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% for both parameters. The description explains the "vector" parameter implicitly ("from a vector string") but says nothing about the second parameter, "input", leaving the agent unable to tell whether the two parameters are aliases, alternatives, or both required. With zero schema documentation, the description needed to disambiguate and does not.

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+resource: "Computes a CVSS base score, impact and exploitability from a vector string." An agent immediately knows this is a CVSS scoring calculator. It does not differentiate itself from plausible neighbors like x402-cve-lookup or x402-cwe-lookup, so it stops short of a 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?

The phrase "from a vector string" implies the input kind, but there is no explicit when-to-use, when-not-to-use, or named alternative anywhere in the description. An agent must infer that this is the scoring step rather than the CVE lookup step.

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