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

With no annotations, the description carries the full burden. It does add useful provenance ("from this server's own hit log, our own checks excluded") and signals a live-measurement nature ("actually serve", "really reach"). It does not state that it is read-only, whether results are cached or how fresh they are, or any cost/rate considerations – gaps that matter for a data-gathering call.

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?

It is a single packed sentence, front-loaded with the tool's identity and then the report contents, with zero filler. The clause-heavy structure (multiple "plus which..." additions) makes it slightly dense to parse, which keeps it from a 5.

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 output schema exists, but the description effectively enumerates what the report returns (counts, grades, worst/cleanest sellers, UA/referer data), so an agent knows what to expect. Missing only ancillary details like response format and data freshness for a fully complete picture.

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?

The tool takes zero parameters, so the baseline is 4. The description correctly presents it as a parameterless report; no parameter meaning needs to be conveyed.

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 names a specific resource (x402 seller market report) and enumerates its contents precisely: valid-challenge counts, dead endpoints, grade distribution, worst/cleanest sellers, and hit-log user agents/referers. This is far from a restatement of the name. It does not, however, explicitly distinguish itself from siblings like akari_endpoint_audit or akari_hl_market, which an agent might reasonably consider for similar-sounding checks.

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?

"Use it to decide where placement pays before you spend on promotion" gives a clear, concrete decision context. There is no explicit when-not-to-use guidance or named alternative for endpoint-level checks, which keeps it below a 5.

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