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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds meaningful context beyond that: the check is live against the served certificate and results are not saved, and it enumerates supported ports. It stops short of describing failure behavior or timeouts.

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 tight sentences with no filler. The core behavior (live TLS check, not saved) is front-loaded, followed by the port list.

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 two-parameter tool with rich annotations and no output schema, the description covers the essential behavioral distinction (live vs stored) and supported ports. Minor gaps remain around default port, host format constraints, and error behavior, but nothing critical for correct invocation.

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 0%, so the schema itself contributes no parameter meaning. The description compensates partially by listing ports (443, 8443, 465, 993, 995), which informs the port parameter, and by saying 'public host', which loosely constrains host. It does not clarify whether port is optional, what the default is, or what host formats are accepted.

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 verb and resource — a live TLS check of a host's served certificate — and the qualifier 'not saved' implicitly contrasts it with lookup_ct (historical CT logs). It does not explicitly name lookup_ct or lookup_domain, so sibling differentiation is inferred rather than stated.

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 is implied by 'live TLS check of a public host's served certificate (not saved)', which suggests checking the current served cert rather than historical records. However, there is no explicit when-to-use guidance, no named alternatives, and no mention of prerequisites or exclusions.

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