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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive). The description adds material beyond them: the per-call price ($0.005 USDC, x402/Solana), a direct HTTPS endpoint, and the transformation applied to content. Cost and payment mechanism are exactly the kind of behavioral context annotations cannot express.

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 core purpose and output format, then appends the price and endpoint in a compact second clause. Dense but zero wasted sentences; every clause conveys a distinct fact.

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?

Enumerates the return payload (title, description, language, word count) in the absence of an output schema, and discloses the payment prerequisite. The main missing piece is the behavioral distinction between main and full modes, which matters for correct invocation.

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%, so the baseline is 3. The description repeats that output is 'main content' and 'plain text' but does not explain what 'full' mode does differently or how max_chars affects truncation, so it adds little over 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 (fetch a web page, return main content as plain text) and precisely describes the output shape (boilerplate stripped, bullets, tab-separated tables, plus metadata). It does not distinguish itself from close siblings like html_to_markdown, readability_extract, or url_markdown, leaving the agent to guess which extraction tool to choose.

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 only implied by 'fetch a public web page', which signals the public-only constraint but gives no explicit when-to-use or when-not guidance and names no alternatives. With several sibling URL-extraction tools, the absence of routing guidance is a real gap.

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