x402_health

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

With no annotations, the description carries the behavioral disclosure burden. It clearly indicates that the tool probes a service over the network, expects a 402 response, and does not itself make a payment. It does not describe the exact return format or error behavior, but the core side-effect profile is 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?

The description is two sentences with no filler. The first sentence states the mechanism and expected response; the second explains why it matters. Each sentence earns its place and the most important information is 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 simple health-check tool with no output schema and no annotations, the description covers what is checked, how it is checked, and when to use it. It does not spell out the return value, but 'Check if' strongly implies a boolean or status result, so the omission is minor.

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 100%, with both 'url' and 'name' already clearly documented as alternatives. The description does not add detail beyond what the schema provides, so the baseline of 3 is appropriate.

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 states a specific action ('Check if an x402 service is live and responding with 402 Payment Required') and a clear resource ('x402 service'). It also connects the check to a concrete use case ('before an agent pays for it'), which distinguishes it from sibling tools like x402_search or x402_fetch.

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 gives a clear usage context: use this tool to verify a service is operational before paying. It does not explicitly name alternatives or say when not to use the tool, but the purpose is distinct enough from the siblings that an agent can infer the right situation.

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