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

With no annotations, the description carries the full burden. It implies a read-only check but adds no detail on permissions, error behavior, timeouts, or what the '5 free trial calls per signed wallet' quota means once exhausted. The payment/auth note is a useful hint but far from a complete behavioral picture.

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 short sentences with the purpose front-loaded; the free-trial/emoji line is promotional noise but still communicates a real constraint. No filler prose beyond that.

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 tool with three undocumented, non-required, semantically overlapping parameters, no annotations, and no output schema, the description should at minimum say which argument identifies the target host. It leaves the caller unable to construct a correct invocation without guessing.

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?

Three parameters (host, input, domain) with 0% schema description coverage and none required, yet the description gives no indication which one to supply or how they relate. The overlapping host/input/domain trio is left entirely ambiguous, so the description does not compensate for the schema gap at all.

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: 'Check SSL certificate expiry date.' An agent can tell it is about TLS certificate expiration, which is distinct from siblings like x402-tls-version or x402-ssl-check, though it never explicitly names how it differs from x402-ssl-check.

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?

No guidance on when to use this versus the many neighboring SSL/domain tools (x402-ssl-check, x402-domain-expiry, x402-tls-version). Usage is only implied by the single sentence of purpose; there are no exclusions or prerequisites.

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