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

Annotations already declare readOnlyHint, openWorldHint, and destructiveHint, yet the description adds substantial behavior: enumerated return values, the distinct 'could_not_ask' result never treated as a 'no', tools listed but never called, data sources limited to the named site plus population figures, and no ranking/listing changes. This goes well beyond the structured annotations.

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?

Front-loads purpose and return statuses, then adds behavioral constraints in a compact paragraph. It is dense but every sentence carries useful information; a bulleted return list could improve scanability slightly.

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, read-only live check with no output schema, the description supplies the missing return contract (six statuses, including robots.txt exclusion) and clarifies side effects and data scope. An agent has enough to invoke and interpret the result correctly.

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 coverage is 100% and the url parameter is already documented with hostname/URL and https assumption. The description does not add syntax or format meaning beyond the schema, so the baseline of 3 for high coverage applies.

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 ('Check') and resource ('website LIVE for WebMCP tools') and enumerates return statuses. It distinguishes scope with 'LIVE' and 'does not consult the index', but does not name or contrast with sibling tools find_capability or get_site_report, so sibling differentiation remains implicit.

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 contextual cues: use for a live check where a browser is available, and clarifies it never consults the index or affects rankings. However, it never states when to choose this over find_capability or get_site_report; usage is implied from scope but alternatives are not addressed.

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