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

Beyond the readOnlyHint/openWorldHint annotations, the description discloses the paid nature (from $0.001 USDC), per-tier pricing, the auth model (optional prepaid api_key vs per-call x402 via _meta['x402/payment']), and the two-step payment protocol (call without payment to get the price, then retry with payment). This is unusually rich behavioral context for a network-fetching tool.

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-loads the two most decision-relevant facts (paid, and the use case), then sequences tier options and the payment flow. Dense but every sentence carries information an agent needs; no filler.

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?

No output schema exists, and the description compensates by describing the return format, so an agent knows what comes back. Combined with the cost, tier, and payment-flow coverage, nothing needed to invoke the tool correctly is missing.

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 75%, and the description meaningfully compensates for the bare enum values by explaining each tier's semantics, relative cost, and appropriate use case, plus the role of api_key vs x402 payment. The url and css_selector parameters are already covered by schema descriptions, so the added value centers on the tier enum, which is exactly where the schema was thin.

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 (scrape/fetch) and resource (one specific web page) and further specifies the output shape (clean Markdown, JSON-LD, HTML tables, links). The resource is unambiguously distinct from the dataset-oriented siblings (buy_dataset, list_datasets, preview_dataset), so an agent can route without opening the 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 an explicit when-to-use trigger ('current content of one specific web page') and detailed guidance for choosing among tiers based on page characteristics (cached copy vs normal page vs JavaScript/Cloudflare). It does not state when NOT to use the tool or route to a sibling alternative, so it falls short of a 5.

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