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

With no annotations, the description carries the burden, and it discloses meaningful behavior: the result comes from a direct TLS handshake from the provider's own servers, and it is scoped to public hosts only. It omits failure handling (expired/self-signed certs, timeouts) and rate limits, so it is good but not complete.

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 sentences that are front-loaded with the core purpose and output list, with no filler. The dense field enumeration is justified because there is no output schema, though it makes the first sentence long.

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 and no annotations, the description steps in by enumerating the returned fields (issuer, subject, SAN, validity, days-to-expiry, fingerprint, chain verification) and the data source, which is enough to call it correctly. Error and timeout behavior are the remaining gaps.

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?

The schema documents the single 'host' parameter at 0% coverage, so the description must compensate. It implies the parameter is a hostname on the public internet, but gives no format guidance (host vs. URL vs. IP, port, SNI), leaving the only input under-specified.

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+resource ('TLS/SSL certificate check for any public host') and enumerates exactly what the check produces, so an agent knows precisely what it does and gets back. It is clearly distinguishable from siblings like domain-lookup, email-verify and fx-rates.

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?

Provides concrete usage contexts ('uptime and security monitoring agents, vendor endpoint checks and integration pre-flight'), which gives a clear when-to-use signal. It does not name an alternative or state exclusions (e.g. certificates on private hosts), so it falls short of full routing guidance.

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