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

No annotations are provided, so the description carries the full burden. It does disclose the return contents (issuer, expiry, days remaining, HTTP headers) and adds commercial context ($0.005/call, 5 free trials). However, it doesn't mention error behavior, network prerequisites, or whether the operation is strictly read-only, though that is reasonably inferred for a domain check.

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 two compact sentences with no wasted words. It front-loads the core purpose, then provides return details and cost in an efficient way. Every sentence earns its place.

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 one-parameter tool, the description adequately covers what inputs it takes, what it returns, and its cost model. With no output schema, it explains the key return fields reasonably well. Minor gaps such as domain format expectations or timeout behavior exist, but they are not critical for this simple tool.

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 the single 'domain' parameter is already documented as 'Domain to process.' The description doesn't add format details (e.g., with or without protocol) or examples beyond what the schema provides, so it neither detracts nor adds meaningful value.

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 combines two domain checks: SSL cert validity (issuer, expiry, days remaining) and HTTP headers. It identifies the resource (domain) and the specific outputs, making the purpose concrete. It doesn't use a strong imperative verb, but 'check' is clearly implied, and the combined nature distinguishes it from single-purpose siblings like ssl-check or http-headers.

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 phrase 'Two checks, one call' implies this tool is for when both SSL and header data are needed in a single request. However, it does not explicitly name alternatives or state when not to use it, such as when only one check is required. Usage context is implied rather than explicit.

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