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

With no annotations, the description carries the full burden, and it does disclose the pricing/payment model ($0.005 USD / x402) — genuinely useful behavioral context. However, it omits whether the check makes live requests, rate limits, or what the result looks like, so the disclosure is partial.

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?

One front-loaded sentence with no filler; the cost signal is appended compactly. Slightly list-dense, but every clause identifies a distinct check performed.

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 stops at naming the checks performed rather than indicating the return shape (pass/fail, scores, per-check detail). For a low-complexity single-parameter tool this is adequate but leaves the agent guessing about 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?

There is a single parameter with 100% schema description coverage ('Target domain name or URL (e.g. example.com)'), so the schema already carries the semantics. The description adds no format or normalization guidance beyond what the schema states, which is the baseline 3 case.

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 ('Checks') and enumerates the concrete resources inspected: robots.txt AI rules (GPTBot, ClaudeBot), llms.txt, sitemap access, and AI indexability. This is clearly distinguishable from siblings like check_url_status or check_noindex_status by content, though it never names or contrasts with those siblings.

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?

The description says nothing about when to run this versus alternatives such as check_noindex_status or run_spider_view_scan, which overlap in the crawlability/AI-visibility space. No prerequisites, no when-not-to-use, no workflow context — the agent must infer usage entirely.

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