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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds genuinely useful behavior beyond that: the credit cost (3 credits) and the shape of the result (score, letter grade, per-category breakdown, issues, top fixes). It does not mention latency, async behavior, or failure modes, so it stops short of a 5.

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?

Two tightly packed sentences: the first front-loads the operation, scope, and cost; the second covers return values. No filler, no redundancy with the annotation 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?

With no output schema, the description correctly compensates by describing the return payload (0-100 score, letter grade, categories, issue list, top fixes), which is the most important context an agent needs. The remaining gap is input-side: URL format and api_key expectations are unaddressed for a tool with 0% schema coverage.

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 are two parameters at 0% schema description coverage, and the description says nothing about either. It never clarifies the expected URL format (scheme, trailing path) or what api_key is for or whether it is optional, leaving the agent to guess on both required-input semantics and authentication.

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 operation (full website health audit) on a specific resource (a website URL) and enumerates exactly what is checked: SEO, performance, security headers, SSL, mobile readiness, content, broken links. The enumerated scope plus the return-value list makes it distinguishable from narrower siblings like check_page_seo and check_broken_links without opening their schemas.

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 '(3 credits)' tag gives an implicit cost tradeoff against the cheaper single-purpose siblings, and 'Full ... audit' implies this is the broad option. However, there is no explicit statement of when to choose this over check_page_seo or check_broken_links, and no prerequisites or exclusions are given.

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