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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safe-read profile is covered without help from the description. The description does add that results include a picture and a live demo, which is mildly useful return context, but an output schema exists so this is not essential. No permission or rate-limit details, which is fine for a read-only list.

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, front-loaded with the usage trigger, then the result shape and the handoff to create-site. No filler or repeated schema content.

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 an output schema present and annotations covering safety, the description only needs to convey when to call it and what to do next, both of which it does. The main omission is any hint about the 'category' filter, a minor gap for an optional 0-required-param 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 description coverage is 50%: the 'search' parameter is documented in the schema while 'category' has only an enum. The description alludes to filtering ("matching templates") but never explains how 'search' or the category values (websites/apps/games) shape the results, so it adds little beyond the schema.

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 names the resource (WebTwizz templates) and the outcome (shows matching templates with a picture and a live demo), and contrasts it with the create-site sibling by telling the agent to pass the chosen slug there. The verb is implicit ("shows") rather than a crisp "list", but an agent can still tell this apart from the ~35 other tools.

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 gives an explicit trigger ("when the user wants to start from a ready-made design, or asks what WebTwizz templates there are") and the follow-up action ("pass the chosen slug to create-site as template"). The when-to-use and the workflow handoff are both stated, leaving little to inference.

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