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

Annotations already declare readOnly/idempotent/non-destructive, but the description adds real context beyond them: the data comes from an 'unpaid, never-signing' probe (so no auth or cost is incurred), it is refreshed daily, and attribution is required under CC BY 4.0. That licensing obligation is genuinely useful behavioral information not available anywhere else.

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 compact sentences, front-loaded with what the tool returns before the filtering and licensing detail. The attribution string is slightly awkward inline but earns its place as a usage requirement.

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 compensates by enumerating the returned fields (grade, score, latency, HTTP status, price, network). What is missing is pagination/limit behavior and the volume of results returned, which matters for a list tool.

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 coverage is only 33%, so the description carries extra burden; it mentions host and min_score filtering, which maps to two of the three parameters, but adds no syntax or range detail beyond the schema, and the limit parameter is untouched. Marginal value over the schema, consistent with a 3.

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 (get/return) and resource (x402 endpoint scores) plus the exact fields returned: grade, score, latency, HTTP status, price, network. This is clearly distinct from siblings like get_directory_counts, get_tool and search_tools, which cover unrelated resources.

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 says the tool supports filtering by host or minimum score and implies a freshness model via 'latest ... daily probe', so usage is inferable. However it names no alternatives, no when-not-to-use case, and no guidance on choosing between host vs min_score filtering beyond the schema.

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