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

Goes well beyond annotations: states the 1.5 MB size cap, the 8 s timeout, the exact content it removes (navigation, footers), and the robots.txt compliance constraint. Annotations only say read-only/open-world; the description adds all the operational limits an agent needs.

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?

Four tight sentences, front-loaded with the highest-value fact (what it returns), then limits, then constraints. Every clause carries decision-relevant information; nothing is padding.

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 single-param, read-only fetch tool with no output schema and only open-world/read-only annotations, the description supplies all the missing operational detail — output shape, size/time limits, JS and robots.txt constraints.

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?

One parameter with 100% schema coverage, so baseline is 3. The description adds that the URL must point at a static HTML page (robots.txt-respecting, no JS), which gives the URL argument real acceptability semantics beyond the schema's terse 'Page URL to convert.'

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?

Specific verb (fetches) plus resource (web page), and it names the concrete output (clean Markdown) along with exactly what it strips. It is trivially distinguishable from every sibling (bank_days, domain_dns, iban_check, site_audit), none of which fetch-and-convert web pages.

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?

Clear operational context: static HTML only, no JS rendering, honours robots.txt — an agent can tell when the page is in scope. It stops short of naming alternatives (e.g. a browser-rendering or site_audit sibling) for JS-heavy pages.

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