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

Annotations only say read-only/open-world; the description adds the operational profile an agent actually needs: public HTTPS only, a 5 second per-request limit, a response size cap, no credentials or payment sent, three-request median latency, and an Ed25519 signed receipt. It also discloses the cost model (0.10 USDC on Base via x402 exact, 10 signed-wallet free calls per rolling 30 days) and the X-Wever-Wallet-Proof binding requirement, none of which the annotations convey.

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?

It is front-loaded correctly — purpose and inputs first, then report contents, then limits, payment and links — and nearly every sentence carries actionable information, particularly the report-field enumeration that substitutes for an absent output schema. The cost is a dense single-paragraph wall of text with heavy semicolon chaining that makes the report-field list harder to scan than it needs to be.

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?

With no output schema, the description carries the return-value burden and does so fully: score composition (reachability, TLS, protocol, latency, consistency), status code, certificate result, handshake details and tool count, x402 challenge well-formedness, median latency, auth behavior, and checked-at time. Combined with the disclosed rate limits, cost, auth proof and contract link, an agent has everything needed to call it and interpret the result.

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 all three parameters are already documented, including the kind enum's auto/mcp/x402 behavior. The description restates the same facts (HTTPS url, optional label, optional kind) without adding format or constraint detail beyond the schema, 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 opens with a specific verb and resource: 'check one MCP server endpoint or x402 HTTP endpoint live'. It names both supported target types and, via the kind parameter, the two check modes, so an agent can tell this apart from sibling diagnostics like wever_listing-check or wever_callback-health-monitor without opening a schema.

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?

Usage context is clear: it validates a live public HTTPS endpoint for MCP handshake or x402 payment-challenge behavior, and the kind semantics ('auto reads the endpoint first and then tries the MCP handshake unless it asked for payment') give real selection guidance. What is missing is any explicit routing versus sibling checks (e.g. directory-status, listing-check) or a stated when-not-to-use condition.

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