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

With no annotations, the description carries the full burden and does well: it discloses the exact price ($0.002 USDC on base via x402), that no account/API key/invoice is needed, and the x402 payment handshake. It omits return format, result limits, and any rate/error behavior.

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?

Three sentences with no egregious waste, but the ordering is weak: it opens with the vague label 'Tool finder' and buries the actual purpose (searching published tool lists) at the very end, after the pricing boilerplate. Front-loading the core function would help.

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, so the description should describe what a result looks like, and it does not — an agent learns nothing about the response shape or result count. The payment flow and pricing are covered adequately, but the return-value gap leaves it only minimally complete.

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 both parameters are already documented. The description reinforces the payment mechanic (omit vs supply `payment`) but adds no new semantics beyond what the schema states, so the baseline 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?

The description names a specific verb+resource ('Find services by the tools they actually publish') and even quantifies scope ('6,530 services'). The 'searching the real tool lists... rather than their marketing text' clause distinguishes it somewhat from the marketing-oriented siblings, though it never names an alternative like search_agents.

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?

It gives an explicit two-step invocation flow: call without `payment` to receive requirements, then call again with `payment` to be served. That is clear context for how to use it, but there is no guidance on when to prefer this over sibling search tools such as search_agents or cheapest_that_works.

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