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

Annotations already declare this is a non-destructive, non-read-only, open-world mutation. The description adds real behavioral value beyond that: it explains that the tool registers the domain and hands back DNS records the user must set at the registrar, plus that verification is a separate step.

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 with the trigger stated first and the side-effect/follow-up in the second clause. No filler, though the second sentence packs three ideas (add, DNS records, verification) into one dense clause.

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 and the description correctly doesn't re-explain the return payload, though it does hint at it (DNS records). For a low-complexity 2-param mutation it is nearly complete; it omits edge cases like domain-already-connected or invalid domain errors.

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%: domain is documented in the schema, site_id is not. The description reinforces that the domain is user-owned ('a domain they already own') and implies site_id is the target WebTwizz site, but adds no syntax or format detail the schema doesn't already carry.

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?

Names a specific verb (connect), resource (a domain the user already owns), and target (their WebTwizz site), and states the side effect (adds it and returns DNS records). An agent can act on this 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?

Gives a concrete trigger condition ('when the user asks to connect a domain they already own') and routes to the follow-up sibling check-domain for verification. It stops short of stating when NOT to use it (e.g., versus set-site-address or a domain that isn't yet owned).

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