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

Beyond the readOnly/idempotent annotations, it discloses substantive behavior: unknown grades, prices and health stay unknown rather than being inferred; payment-ready only reflects a recent valid unsigned challenge and does not certify paid delivery; cursors are immutable but current privacy controls still apply; and it never signs payments. These are exactly the caveats an agent needs to interpret results without over-trusting them.

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 purpose leads, and the caveats follow in short declarative sentences with little filler. A couple of lines are telegraphic to the point of ambiguity ("Unknown grades, prices and health remain unknown"), but nothing is padded.

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 13 optional parameters, 0% schema descriptions and no output schema, the definition covers the trust/safety dimension well but leaves the retrieval mechanics thin: no guidance on limit/pagination behavior via cursor, no notion of what a result row contains or how sorting interacts with cursors, and no meaning for featured or include_delisted.

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 0% for 13 parameters, so the description has to carry the load. It touches many facets (text, host, category, network, source, tier, grade, owner control, cursor) and defines the tier values, but leaves sort, limit, featured, and include_delisted unexplained, and gives no syntax or matching semantics for text/host.

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?

Uses a specific verb plus resource ("Find x402 services imported from attributed catalogs or scanned by Mekler") and characterizes the corpus being searched, which is more than a tautology of the name. It does not, however, draw the boundary against the sibling search_services, so an agent must guess which of the two search entry points to call.

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?

"Filter by task text, host, category, network, source, tier, grade or owner control" enumerates the facets, which implies when the tool is useful, and the payment-ready definition helps an agent decide on the tier facet. But there is no explicit when-to-use / when-not guidance and no named alternative among siblings such as search_services or retrieve_listing.

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