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

Annotations already declare readOnlyHint and openWorldHint, and the description adds meaningful context beyond them: payment terms ($0.02 USDC per call via x402 on Base or Solana), that the data is signed, that rankings are never for sale, and that the method is included. It stops short of describing return shape, pagination, or rate limits, keeping it at a strong 4.

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?

Front-loaded with the resource and what the boards contain, followed by the parameter behavior and payment terms. It is dense and uses fragments, but nearly every clause carries distinct information; slightly run-on in the parenthetical flag list.

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 read-only, single-optional-parameter tool with no output schema, the description covers what is returned (the three board types plus flags), how the data is derived (method, wash-adjusted), the trust signal (signed, not for sale), and the access cost. An agent has everything needed to decide and invoke.

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%, so the description must carry the parameter's meaning, and it does: category= scopes the result to one vertical and gives concrete examples (shopping, ai-inference, crypto-data). It also implies the parameter is optional by presenting the unfiltered boards as the default. Format details for the value are left unstated, so not a 5.

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 specific verb and resource ('Leaderboards from our independent checks of x402 services') and enumerates the exact boards returned: most real wash-adjusted paying customers, most reliable, and flagged services. This clearly separates it from sibling per-entity tools like checks_service and checks_seller, which cover a single service rather than a ranked board.

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?

The description explains the optional category= filter ('one category's boards') which guides a usage decision, but never states when to prefer this leaderboard view over checks_service or checks_seller. Usage is implied by the nature of the output rather than explicitly contrasted with alternatives.

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