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

Annotations already cover read-only, idempotent, open-world safety. The description adds genuinely new behavioral facts: it respects robots.txt, performs soft-404 detection, checks size, and costs $0.005 per call via x402 payment. It does not describe what the response looks like, which matters since there is no output schema.

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 the core check, then validation criteria, then usage timing and pricing. Dense but nearly every clause carries information; the enumerated validation rules are slightly compressed into one long sentence.

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, so the description should imply return content; it enumerates the checks (H1, blockquote summary, H2 sections, link lists, soft-404, size) which indirectly signals results, but it never states the response shape (pass/fail, findings list). Otherwise complete for a single-parameter read tool.

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 there is only one parameter, which the schema already documents with an example. The description adds no format or edge-case meaning beyond 'domain', so the baseline 3 is appropriate.

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: checks whether a domain publishes /llms.txt and /llms-full.txt and validates structure against the llmstxt.org spec. The scope (presence + structure validation) clearly separates it from siblings like geo_audit or ai_crawler_matrix.

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 before or after publishing an llms.txt file" gives a concrete trigger context. It does not name an alternative tool or state when not to use this one, 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.