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

With no annotations, the description carries the safety burden. It implies a non-destructive read-only check ('before you pay it', 'verifies', 'inspects') and explicitly mentions live on-chain and network activity. It could be more explicit about potential side effects like RPC calls or latency, but it conveys the operational scope better than most descriptions.

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 dense sentences pack a high amount of information without fluff. The first sentence is a long list but logically organized; the second handles return values. It could be broken into bullets for readability, but it is efficient and front-loaded.

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 compound tool with no output schema, it explains return values (score, verdict, evidence) and lists all major checks. It lacks explicit detail on what 'market baselines' or 'infra hygiene' entail and doesn't mention error handling, but the core behavior and outputs are adequately covered.

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?

The schema has one param (url) with zero description coverage, so the description must add meaning. It repeatedly references 'the endpoint' and specifies 'x402-metered endpoint', clarifying the expected URL type beyond the generic uri format. It doesn't explicitly define the parameter, but it is strongly implied.

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 clearly states the tool's purpose: running live diligence on an x402-metered endpoint before payment. It enumerates specific checks (402 compliance, price baselines, on-chain payTo inspection, directory presence, infra hygiene, resale detection) and describes the output, making it unmistakable and distinct from narrower sibling tools.

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 phrase 'before you pay it' provides a clear usage context (pre-payment verification), and the list of checks implies when this tool is appropriate. However, it does not explicitly contrast with sibling tools like compare_price or reseller_check, nor state when not to use it.

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