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

Beyond readOnlyHint/openWorldHint it discloses the matching algorithm (case, spacing, quote and dash styles ignored), that matching is deterministic ("No AI involved"), the failure billing policy ("if the page can't be read you are not charged"), and the exact cost mechanism ($0.01 USDC per call via x402). That is unusually rich operational context for an agent deciding whether to spend a call.

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, front-loaded with the core behavior, then the use case, then cost/failure semantics. No filler and nothing repeated from the schema.

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 partially compensates by stating the return ("the surrounding text"). It does not describe the response shape per quote or how misses are represented, which is the main remaining gap for an agent parsing results.

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%, so url and quotes are already documented; baseline would be 3. The description adds meaning beyond the schema by stating the 1-10 count limit and the normalization rules, which tell the agent it need not reproduce exact punctuation or spacing when building the quotes array.

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 precise verb+resource: verifying that 1-10 quotes literally appear on a given URL, plus the normalization rules applied and the returned surrounding text. The scope is distinct from siblings like check_doi (citation identity) and page_text (raw extraction), though no sibling is named 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?

"Use it to catch made-up citations" gives a concrete when-to-use context, and the 1-10 quote bound implies batching. There is no explicit when-not or pointer to an alternative (e.g., check_doi for DOI resolution), so it stops short of full routing guidance.

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