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

Annotations already cover safety (readOnlyHint=false, destructiveHint=false, idempotentHint=false, openWorldHint=true), and the description goes beyond them by disclosing the no-account auth model and enumerating what comes back: page rules, viewable address, and a file-saving key. It does not address limits such as whether one site can be started per person or what happens on repeat calls.

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?

Three short sentences, front-loaded with the action and the no-account precondition, then the return payload. No filler or restated title.

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?

With no output schema, the description correctly takes on the job of listing return values, and it covers auth. The remaining gap is state handling — it doesn't say whether a website may already exist for this person or whether this replaces anything, which matters given idempotentHint=false.

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 both parameters (about, businessName) are already documented as 'what the person said.' The description adds no format, length, or sourcing guidance beyond that, so the baseline 3 applies.

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?

Uses a specific verb and resource ('Begins a new website') and immediately scopes it to 'the person you are helping,' which is enough to tell it apart from the delete/read/save siblings. It stops short of naming an alternative or stating relationship to an existing site, so it is clear but not maximally differentiating.

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?

'No account is needed' is a useful precondition, but the description never says when to call this versus the alternatives (search_domains, or what to do if a website already exists). Usage is implied by the verb rather than stated.

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