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

Annotations cover the safety profile (readOnly, openWorld, non-destructive), and the description adds substantial detail beyond them: no usage consumed, no AI call, the exact crawl scope (12 pages plus sitemap.xml and robots.txt), the full checklist of what is verified, and honest framing that the score is a Kleap metric rather than a Google metric. This is exactly the kind of context that helps an agent interpret results correctly.

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-loaded with the free/no-cost constraint and scope, then the checklist and return shape, then the remediation workflow. It is dense and slightly long, but nearly every clause carries actionable information, so waste is minimal.

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 an output schema present, return values need not be spelled out, yet the description still summarizes them (score.percent, top3 fixes, findings with impact and fix). Combined with the crawl scope and the cost/auth caveats, an agent has everything needed to call it and interpret the result.

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 url, context and max_pages are already documented. The description reinforces the page-reading behavior ('reads up to 12 pages') but adds no format or syntax guidance beyond the schema. Baseline 3 is appropriate when the schema carries the parameter burden.

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/audit) plus resource (SEO of a public website URL) and immediately scopes it against siblings: 'on Kleap or not (no app_id...)' tells the agent this takes a raw URL rather than an app identifier, unlike the app-scoped siblings. An agent can distinguish it from check_domain or get_search_console without opening a schema.

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?

Gives clear context (free, single public URL, works for non-Kleap sites) and an explicit follow-up workflow for Kleap sites (read_files, edit_files, publish_app, then re-run). It does not name a competing tool or state when NOT to use it, so it falls short of the explicit alternatives/exclusions that earn a 5.

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