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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so the safety profile is covered. The description adds real value by disclosing the transformation behavior: headers, footers, and advertising noise are stripped and output is standardized to CONTENT.md. It does not mention failure modes (paywalls, blocked pages) or how the rate-limit tier affects behavior, so it stays at a 3.

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?

A single well-formed sentence with the action and the noise-stripping guarantee front-loaded, and no wasted wording. It is efficient, though it does not separate primary usage guidance into its own clause.

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?

For a two-parameter extraction tool with no output schema, the definition covers action, source, output format, and what is removed from the result. The main remaining gap is what happens on pages that fail extraction or how the result is delivered, but nothing critical for invocation 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 100% and both parameters carry descriptions, so the baseline of 3 applies. The description adds no meaning beyond the schema for url or api_key, though the api_key rate-limit implication is already stated in the schema itself.

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?

The description states a specific verb (extract) and resource (core article or documentation body) and names the output artifact (CONTENT.md), so the agent can distinguish this from a generic converter like url_to_markdown. It stops short of explicitly contrasting itself with that sibling, which keeps it from a 5.

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?

Usage is implied by the phrase 'from any URL' plus the noise-stripping qualifier, which suggests article/documentation pages rather than arbitrary endpoints. There are no explicit when-to-use or when-not-to-use conditions and no guidance on choosing between this and url_to_markdown or the design/links variants.

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