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

Annotations already cover read-only/idempotent/non-destructive/open-world, so the description adds real value on top: the document-vs-page degradation behavior and the cost model ('billed per 10 document pages'). It does not mention rate limits, size ceilings, or how failure on an unparseable document is reported.

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 short sentences: what it does, when to choose it, and the cost/edge-case. The primary behavior is front-loaded and no sentence is 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?

An output schema exists, so return-value documentation is not required, and the safety profile is fully covered by annotations. The remaining gap is the undocumented maxChars truncation semantics, which an agent needs in order to size requests 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 0%, so the description carries the full burden, yet it never mentions 'maxChars' (default 20000) or what happens when the document exceeds it — a critical truncation behavior for a text-extraction tool. Only the 'url' parameter is implicitly explained, via 'a document at a URL'.

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 (read/parse) plus the resource (a document at a URL) and names the output format (text as markdown). It implicitly contrasts itself with page-oriented siblings via 'a link to a document rather than a web page', but never names 'scrape' or another sibling explicitly.

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 a clear selection rule: use this for document links, not web pages, and explains the fallback ('a URL that turns out to be an ordinary page is returned as that page'). It stops short of naming the alternative tool (e.g. scrape) for plain pages, so routing is inferred rather than stated.

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