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

With no annotations, the description carries the burden well: it discloses a hard cost ($5 USDC/call) and payment rail (x402, eip155:8453), signals a non-mutating 'passive' operation, and names the result vocabulary (ok/ko/not_measured) plus an EIP-712 attestation. It stops short of stating timeout behavior, redirect handling, or what happens when the target is unreachable.

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?

A single dense sentence with no filler, front-loaded with the price/payment context an agent needs before calling. The check enumeration is compact, though the bracketed payment prefix plus colon-separated lists make it jargon-heavy on first read.

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 3-parameter, no-annotation, no-output-schema tool, the description covers the essentials: cost, payment mechanism, the full check surface, and the possible result values. The only residual gap — how to verify the EIP-712 attestation — is covered by the sibling verify_attestation.

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%, so the schema already documents url, expect_text, and max_response_ms. The description only echoes 'optional expected text' and 'internal links sample', adding no format or constraint detail beyond what the schema provides — baseline 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 and resource ('Signed passive website proof') and then enumerates exactly what is checked: reachability, TLS certificate, http→https, response time, title, mixed content, real 404, internal links sample, expected text. That enumeration clearly separates it from broad auditors like site_audit_full or seo_technical_audit, though it never names a sibling explicitly.

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?

There is no statement of when to use this instead of site_audit_quick, test_seo, or x402_probe, and no exclusions or prerequisites beyond the implicit 'passive' framing. An agent must infer the use case entirely from the check list.

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