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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is known. The description adds meaningful behavioral context by naming the audit domains and stating the return format: a 0-100 score plus prioritized issues with fixes. It does not mention authentication, rate limits, or depth of crawling.

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 front-loaded with the core purpose and then lists audit coverage, which is useful. The long parenthetical enumeration is dense but each item contributes to understanding the audit scope, so it remains reasonably concise.

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 appropriately states that it returns a 0-100 score and prioritized issues with fixes. For a single-parameter, read-only tool, this is enough to call it correctly, though additional differentiation from sibling tools would improve 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?

There is only one parameter, and schema description coverage is 100%, so the URL format is fully documented in the schema. The description adds no additional parameter-level semantics beyond what the schema already provides, which matches the baseline for high-coverage schemas.

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 and resource ('Classic SEO audit of a page') and enumerates the audit dimensions covered. It is clear what the tool does, though it does not explicitly differentiate itself from siblings like audit_ai_visibility or check_core_web_vitals.

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 'Classic SEO audit of a page' implies usage for a comprehensive page-level audit, but there is no explicit guidance on when to use this versus the narrower sibling tools. The agent must infer the boundary from the list of covered areas.

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