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

Annotations already carry destructiveHint=true and openWorldHint=true, so the safety profile is known. The description adds real behavioral value beyond them: a live site moves to the new address and the old one redirects 'for a while,' which tells the agent the operation is not an instant full cutover. It stops short of stating how long the redirect lasts or whether the new name can collide with an existing one.

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, both earning their place, with the usage trigger front-loaded ahead of the behavioral caveat. No filler.

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?

An output schema exists, so return values need not be described, and annotations cover the safety profile. The description supplies trigger and redirect behavior, leaving only site_id and redirect duration unaddressed for a simple two-parameter tool.

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 coverage is 50% (name documented, site_id not). The description reinforces the name parameter's meaning via 'the name before .webtwizz.app,' matching the schema's own example. It adds nothing for site_id, so it doesn't compensate for the coverage gap.

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+resource (change the site's free address) and pins down exactly what 'address' means: the name before .webtwizz.app. This scope disambiguates it from the domain-oriented siblings like connect-domain and check-domain without opening their schemas.

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?

'Use this when the user wants to change their WebTwizz site's free address' gives a clear triggering condition. The 'free address' qualifier implicitly excludes custom-domain changes handled by connect-domain, but no alternative or exclusion is named explicitly.

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