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

With no annotations provided, the description carries the full burden. It does disclose useful behavior: the catalogue is 'live,' the return payload fields, and a bounded result count ('limit 1-20'). It omits whether the operation is read-only, whether auth/payment is required, and any pagination or rate-limit behavior, so it is partially but not fully transparent.

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 tight sentences with the purpose and return shape front-loaded and no filler. It loses a point only because the trailing parameter note is thin and slightly at odds with the schema's string-typed limit.

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?

For a 6-parameter tool with no annotations and no output schema, the description covers too little: the four alias-like search parameters are undocumented here and in the schema, and there is no mention of auth/payment context for a 'live' paid catalogue. It is not adequate to call the tool correctly without guesswork.

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% across 6 parameters, so the description must compensate. It only addresses q and limit and leaves text, query, search, and keyword completely unexplained, so an agent cannot tell whether these are aliases for the same query input or distinct fields. It also declares 'limit (1-20)' while the schema types limit as a string, adding confusion rather than clarity.

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 verb and resource ('Keyword search over the live x402 service catalogue') and enumerates the returned fields (ids, names, endpoints, prices), so an agent can tell what the tool does at a glance. However, siblings like x402-search and service_discovery exist and the description does not distinguish this tool from them, leaving the agent to guess which catalogue-search to pick.

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?

There is no guidance on when to use this tool versus alternatives such as x402-search, service_discovery, or x402-token-search, and no prerequisites or exclusions are stated. The agent gets a purpose but no routing logic.

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