Check a domain's HTTPS/TLS configuration

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

Despite annotations stating readOnlyHint=true and idempotentHint=true, the description transparently discloses that the tool is NOT passive and triggers an active assessment from Qualys's infrastructure, which is a behavioral nuance beyond what annotations convey. It also clarifies it does no port scanning or exploit testing itself, and mentions it reuses cached results when available. This fully discloses the external side effect and safety profile without contradicting annotations—'readOnly' is still true in the sense of not modifying the target.

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?

The description is well-structured and front-loaded with the core purpose, then lists specific findings, then warns about the active nature (critical for agent decision-making), and finally clarifies exclusions and sibling differentiation. Every sentence adds value, and the length is justified by the need to convey the active behavior and scope boundaries.

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 one parameter and no output schema, the description is complete: it states what it returns (grade and specific findings), what it does NOT return (expiry, issuer, hostname validity), how it operates (external active assessment), and when to use it. It also covers edge cases (cached results) and exclusions. Nothing an agent needs to decide whether to call it and interpret results is missing.

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 already provides a thorough description of the 'domain' parameter: accepted formats, normalization, and explicit exclusions. The tool description adds no additional parameter-level semantics beyond what the schema states. Since schema coverage is 100% and the parameter is simple, the baseline of 3 applies—no further clarification needed.

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 precisely what the tool does: it answers whether a domain's TLS configuration has known weaknesses, returns the Qualys SSL Labs grade, and lists specific vulnerabilities it checks (Heartbleed, POODLE, RC4, etc.). It also distinguishes itself from siblings by explicitly saying it does NOT check HTTP security headers (use check_security_headers) and does NOT report certificate expiry/issuer/hostname validity, so an agent can differentiate it clearly.

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?

The description gives explicit when-to-use guidance: prefer it for a domain you own or are authorized to test, and warns it is NOT passive because it causes a third-party active assessment. It also provides exclusions (do not pass IP, email, private hostname) and points to the alternative tool for headers, plus suggests reading the certificate directly for expiry/issuer needs. This is complete routing guidance.

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