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

Annotations already declare readOnlyHint=true, so the safety profile is covered; the description adds real substance by enumerating the exact evidence classes (security.txt directives, CVD policy, CSAF, SBOM, support period) that define a "readiness" result. It does not explain what happens when a domain exposes none of these (empty result vs. failed checks), nor what the response shape looks like. The declared openWorldHint=false also sits in mild tension with a tool that inspects arbitrary external domains, though the description itself is not the cause of that inconsistency.

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?

One sentence, purpose front-loaded before the colon, and every item in the list is a distinct check the agent can reason about. Nothing is padded or repeated from the title.

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 single-parameter, read-only scan with no output schema, the description covers what is inspected and against which two regulations, which is what an agent needs to select the tool. The remaining gap is that it never indicates the shape or granularity of findings (pass/fail per artifact vs. raw extracted records), so output must be discovered at call time.

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?

There is a single required parameter and schema description coverage is 100%, so the schema already carries the burden. The description adds only the framing that the domain is a *vendor* domain under regulatory assessment, not any format, normalization, or subdomain-handling guidance. Baseline 3 is appropriate.

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?

Names a specific verb ("Scan") and resource ("vendor domain") and scopes it to two named regulatory regimes (EU CRA, UK PSTI), then enumerates the concrete artifacts examined (RFC 9116 security.txt fields, CVD policy, CSAF provider metadata, SBOM, support-period statements). None of the sibling tools overlap, so no disambiguation is needed and an agent can tell exactly what this returns evidence about.

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 "vendor domain" implies the intended scenario (assessing a supplier's disclosure readiness), but there is no explicit when-to-use, when-not-to-use, or routing to an alternative tool. It also doesn't state prerequisites such as the domain needing to be publicly reachable. Usage is inferable but not guided.

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