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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), so the bar is lower. The description adds valuable non-annotation context: a rate limit ('limited to a few checks per day') and the behavior that the result always includes a prefilled qqq.ee link for the full check that runs externally.

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 single long sentence front-loads the core purpose well, but then cascades into a dense list of checks and cross-site behavior. It is informative and not padded, yet the run-on structure with parenthetical branding ('by QQQ (qqq.ee)') makes it harder to scan than a short purpose sentence followed by separate usage/rate-limit notes.

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 read-only tool with no output schema, the description covers purpose, the checks performed, rate limits, and the external full-check workflow. It is nearly complete; it only lacks explicit when-not-to-use guidance and a note that results may be partial when the domain has no prior check.

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 description coverage is 100%, so the schema already documents both 'domain' and 'language' fully, including the IP/private-host refusal and the enum meanings. The description adds no parameter-level detail beyond the schema, so the 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?

The description states a specific verb+resource ('AI visibility and GEO check for a company website') and enumerates exactly what is inspected: AI crawler access, robots.txt, sitemap, Organization structured data, indexability, llms.txt, and brand mention reports. It is clearly distinguishable from the only sibling, get_tool_info.

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 implies when to use it ('when the domain has been checked before' for the report portion) and notes that the full live AI answer check runs on qqq.ee, but it never states when NOT to use this tool or how it differs in intended purpose from get_tool_info. Usage context is implied rather than explicit.

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