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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds substantial behavioral context beyond annotations: it discloses that the tool identifies typos matching no known crawler, separates crawlers that document obedience from those observed ignoring robots.txt, and evaluates per path. It also reveals the same implementation is callable via HTTP, which is important behavioral information for an MCP agent.

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?

The description is efficient and front-loaded with the first-call instruction and an immediately usable JSON-RPC payload. It is longer than the average description, but every sentence earns its place by describing return categories, typo identification, obedience behavior, and fallback advice. The structure leads with the most actionable information, though the inline JSON-RPC example adds length that might distract from the core purpose.

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?

For a read-only analysis tool with no output schema, the description is remarkably complete. It tells the agent what inputs to provide, what the verdicts mean, how to interpret unknown tokens, and what follow-up action may be needed (IP/WAF rule). It even provides an HTTP fallback invocation. There is no output schema, so the description's detail about the two lists and the typo report compensates adequately.

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 schema already documents both parameters. The description adds value by clarifying the robots_txt parameter is the full file contents to paste, that path defaults to '/', and that the verdict is per-crawler at that path. It does not duplicate the schema verbatim and adds a concrete example showing what a pasted robots.txt looks like.

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 very specific verb-resource pair: evaluate a pasted robots.txt against every AI crawler in the index, returning blocked/ allowed lists per operator and category. It also explicitly differentiates itself from sibling tools by describing what it does rather than what related tools do, and it names the alternative entry point 'no_arguments_lint_this_hosts_robots_txt' as the FIRST CALL, making its purpose and relationship to siblings clear.

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 explicitly tells the agent when to use it: it is the FIRST CALL, needs nothing, and should be used to evaluate a pasted robots.txt. It also states when an alternative path is needed: crawlers observed ignoring robots.txt need an IP or WAF rule instead. It names the sibling no_arguments_lint_this_hosts_robots_txt and the no-MCP HTTP equivalent, so usage context is explicit rather than implied.

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