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

Annotations declare readOnly/openWorld/destructive=false, but the description adds substantial context beyond them: breadth-first traversal of same-site links, a 20-page ceiling, that results carry title and description, the billing rule ('charged only if at least one page was read'), and the full x402 payment model with chains and price. This is exactly the behavioral disclosure the annotations cannot supply.

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 purpose and alternatives, then params, then pricing. Dense but nearly every clause is load-bearing for a paid tool (payment path, free sample). It is longer than typical, but little is pure 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, yet the description explains the return ('up to 20 pages with title and description'), the traversal scope, the cost/billing condition and how payment is settled. Combined with usage routing and param guidance, an agent has everything needed to call it correctly.

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 only 25% (just path_prefix), so the description must compensate, and it does: it marks url as required and enumerates max_pages (1-20, default 5), max_chars per page (500-20000, default 4000) and path_prefix with an example. It clarifies that max_chars is per page and supplies the '/docs' style example, though the numeric ranges largely duplicate the schema.

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 ('website crawler: read a whole website or one section of it... as clean Markdown') and immediately names what it is not: the alternatives web-scrape, web-read-batch and web-scrape-batch. An agent can distinguish it from every sibling 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?

Explicit when-to-use cases ('documentation, product catalogs or company sites') plus explicit routing rules to alternatives ('For one page use web-scrape, for a known list of URLs web-read-batch (up to 5) or web-scrape-batch (up to 20)'). Both the positive selection condition and the alternatives are stated.

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