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

Annotations only declare the generic profile (readOnlyHint=false, openWorldHint=true, idempotentHint=false, destructiveHint=false). The description adds substantial behavior the annotations cannot convey: asynchronous execution (returns a scanId immediately rather than results), the required polling cadence and termination condition, plan gating, and a real cost model ('each checked page uses 1 page of the monthly allowance').

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?

Three sentences, front-loaded with what it does, then eligibility/routing, then the async follow-up and cost. Every clause carries operational information — no filler or restated title.

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?

An output schema exists, yet the description still supplies the one thing an agent needs to act on the result: that the response is a scanId requiring polling via get_scan with a 10-second interval. Plan restrictions and quota consumption complete the picture for a long-running, allowance-consuming operation.

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% and both parameters are documented in the schema, so the baseline is 3. The description restates the same clamp semantics already present in maxPages' schema description ('clamped by the account allowance and page limit') and adds no format, syntax, or default information beyond it.

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 and resource ('crawl a public website from its root URL and proofread every page found') with explicit scope limits (maxPages, plan page limit). It also names the sibling it is not — 'for one page, use proofread_url' — so an agent can distinguish it from proofread_url and get_scan without reading schemas.

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 explicit eligibility ('Pro and Ultra plans only'), an explicit alternative-selection rule ('for one page, use proofread_url'), and the follow-up workflow ('call get_scan with it every 10 seconds and stop when done is true'). When-to-use, when-to-use-something-else, and what-to-do-next are all covered.

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