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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so safety is covered. The description still adds real behavioral context beyond them: it is free, takes a few seconds, and is scoped to exactly three artifacts, which tells the agent what the result will and will not reflect.

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?

Two sentences, no filler; the core purpose and the enumerated checks lead, and the exclusions follow. Every clause carries information the agent needs, and the crawler list is compactly delivered.

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?

There is no output schema, so the description carries the return-value burden, and it does: it names the exact signals returned (crawler rules, llms.txt, title, meta description, JSON-LD types). Combined with the stated exclusions and cost/latency note, an agent has everything needed to call and interpret it.

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% and both parameters are documented in the schema, including the domain example and the language default/enum. The description adds no parameter-level detail (it never mentions the language option or domain format), so this is the baseline 3 where the schema does the work.

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 and resource ('Checks whether a website is technically open to AI assistants') and then enumerates exactly what is inspected: robots.txt rules for nine named crawlers, llms.txt presence, and home-page title/meta/JSON-LD. No siblings exist, but the scope is precise enough that an agent knows the tool's boundary without opening the schema.

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?

It gives an explicit negative boundary ('does NOT measure whether any AI assistant actually recommends the brand') and names the alternative that covers that case (the paid GEO-bot check), plus the surface-area limit (home page, robots.txt, llms.txt only). It stops short of stating a positive 'use this when...' trigger, so it is strong but not fully exhaustive.

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