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

The description adds significant behavioral context beyond annotations: it warns that certificate data comes from Certificate Transparency logs and 'may differ from the one currently served.' It also explicitly states what is excluded (TLS protocol versions, cipher suites). Annotations already indicate readOnlyHint, idempotentHint, non-destructive, so the description complements them without contradiction.

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 concise and front-loaded with the core purpose. It efficiently covers scope, data source caveats, and exclusions in 4 sentences. Minor redundancy: 'read from public Certificate Transparency logs' could be tighter, but overall well-structured.

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?

Given the output schema exists (the score mentions 'has output schema: true'), the description does not need to detail return values. It covers key behavioral aspects (caveats, exclusions, usage). However, for a tool with 3 parameters and potential caching nuances, a brief note on default caching behavior or typical latency could strengthen completeness.

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 100%, so baseline is 3. The description adds minimal value beyond the schema: it mentions 'domain' implicitly through 'Check the HTTPS/TLS posture of a domain' and notes the force_refresh is 'Useful after DNS changes' in the schema itself. No new semantic insight is added beyond what the schema provides.

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 clearly states the tool's purpose: 'Check the HTTPS/TLS posture of a domain' and lists specific checks (HTTPS reachability, HSTS policy, redirect, certificate metadata). It differentiates from siblings like check_http_security and scan_domain by mentioning it is 'Part of the scan_domain audit,' but does not explicitly distinguish from all reading-related siblings.

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 provides explicit usage context, e.g., 'Use to verify HTTPS/HSTS configuration and certificate issuer/expiry.' It also mentions what is NOT returned (negotiated TLS protocols), which guides agents away from expecting that data. However, it does not explicitly state when NOT to use this tool or provide alternative sibling names.

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