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

Adds real information beyond the readOnlyHint/openWorldHint annotations: a concrete price ($0.20 USDC per call on Base via x402) and the failure-billing policy (not charged if the call fails), plus the conditional outbound fetch. It does not disclose latency, rate limits, or what the returned score looks like, but the payment semantics are the highest-value missing piece and are covered.

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 padding: what it returns first, then cost and billing policy. The payment caveat is a sentence fragment that still carries essential decision information, and nothing is repeated from the schema.

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?

Covers the two things an agent most needs to decide and act: the paid-call cost model and the optional fast path. For a read-only scoring tool with no output schema, the main remaining gap is what the score means (range, components, confidence), which would help interpretation but not invocation.

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 handle, platform enum, and the optional profile object are all already documented. The description repeats the fetch-skipping behavior of `profile` without adding format, size, or required-fields detail for that nested object, so the baseline of 3 applies.

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 concrete output (a vetting score) for a concrete resource (one creator profile), which separates it from siblings like ad_creative_score (ads), ai_visibility (AI search), and company_enrich (companies). The verb is implicit in "vetting score" rather than a stated action, but the resource and scope are unambiguous.

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?

Usage is only implied: "for one profile" signals a single-creator operation, and "fetches the profile if stats not supplied" hints at the optional-profile path. There is no explicit when-to-use statement, no conditions favoring siblings, and no note on when a batch or alternate tool would be preferable.

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