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

Annotations already declare readOnlyHint, openWorldHint, and destructiveHint, so safety is covered. The description adds nothing behavioral beyond that: it does not say what happens when a page has no structured data, whether validation errors vs warnings are reported, or whether the page must be publicly reachable.

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, front-loaded with the action and resource, with zero filler. Nothing could be cut without losing meaning.

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 simple single-parameter read-only tool this covers the core intent, but with no output schema the description should have sketched the return shape (e.g., detected types, validity/error list). That gap leaves the agent unsure what result to expect.

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 parameter with full schema description coverage ('The URL to analyze.'), so the schema already carries parameter meaning. The description adds nothing about URL form (absolute vs relative, http/https) or content-type expectations, so the baseline 3 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 pair (detect and validate) and a specific resource (JSON-LD / structured data on a page). This is clearly distinguishable from siblings like analyze_meta_tags, check_open_graph, and check_hreflang, each of which targets a different markup surface.

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 description gives no when-to-use or when-not-to-use guidance and never names an alternative. An agent must infer from the tool name alone whether this belongs in a broader SEO audit or is a standalone check.

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