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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), so the description's added value is its disclosure of source scope (homepage + up to 25 declared pages, using titles/descriptions) and the caveat that output is a draft, not a finished artifact. It stops short of stating auth or rate-limit behavior, but adds genuinely useful context beyond the annotations.

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 tight sentences, front-loaded with the action and scope, followed by the output caveat. Every clause carries information; nothing is redundant.

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 one-parameter tool with no output schema and annotations already carrying the safety profile, the description covers what it reads and roughly what it produces (an internal draft). It could say a bit more about the returned artifact's shape, but it is largely sufficient to call the tool correctly.

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 0% for the single 'domain' parameter, so the description must compensate. It clarifies that the domain is fetched via its own homepage, which tells the agent the parameter is a live fetchable domain, but gives no format example (e.g., bare hostname vs URL), leaving some ambiguity.

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 uses a specific verb ('Draft') plus resource ('llms.txt') and states the exact inputs it derives from: the domain's homepage and up to 25 declared pages, using their titles and descriptions. No sibling tool does this, so an agent can identify it immediately 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 frames the output as 'a draft for the owner to cut down, not a publication,' which implies intended use, but it never states when to run this versus alternatives like scan_domain or resolve_robots, nor any prerequisite (e.g., that the domain must already be crawled/scanned). Usage context is therefore only implied.

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