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

Annotations already declare readOnly/openWorld/no-destructive, so the safety profile is covered; the description adds meaningful behavior on top — the fallback to rendered HTML when no structured data is found and that this fallback is billed like fetch_html. It leaves out latency, rate limits, and failure modes, so it is good but not exhaustive.

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?

Two sentences, zero waste: the primary purpose and return type come first, the edge-case fallback and its billing implication second. Everything is front-loaded and each clause earns its place.

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 carries the return-value burden and does so well by naming the JSON categories and the HTML fallback. It is nearly complete for a 2-parameter read tool, missing only detail on how the 'no structured data' signal is surfaced in the response.

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 coverage is 100% and both parameters (url, proxy_country) are fully documented in the schema, so the baseline is 3. The description adds no extra meaning about the URL format or what proxy_country changes about the fetch.

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+resource (fetch a web page and return AI-parsed structured JSON) and explicitly contrasts the return type with raw HTML, which cleanly separates it from the sibling fetch_html. The parenthetical examples of structured payloads (product details, article content, listings) make the resource scope concrete.

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?

It names the alternative (fetch_html) and the condition under which the result degrades to it, giving the agent a decision rule. It doesn't state when to prefer fetch_html outright or preconditions such as auth/rate limits, so it falls short of an explicit when/when-not pair.

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