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

Annotations already declare a non-readonly, non-destructive, non-idempotent mutation; the description adds real context beyond that by listing copied fields, the excluded domain/published state, and that the copy is immediately active. It doesn't spell out that repeated calls create additional copies, but the 'becomes active' wording makes the create-new-resource effect clear.

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 compact sentences: copy scope first, exclusions second, resulting state and response third. No filler, and the most decision-relevant information is front-loaded.

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 usefully reports what the result contains (editor link, previewUrl), and it covers both included and excluded fields of the copy. It omits error/permission conditions and idempotency implications, which keeps it just short of fully complete.

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 100%, so id, name, title and description are already documented in the schema, which sets the baseline at 3. The description reinforces that title/description are overrides on the copied values, but says nothing about the 'name' slug or that id is the source identifier beyond what the schema states.

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?

Opens with a specific verb+resource ('Copy a site') and enumerates exactly what is copied (content, title, description, portal, crawlPolicy), which separates it from create_site or import_site. It stops short of naming those siblings, so the distinction is inferred from the verb rather than stated.

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?

The negative scoping ('Domain and published state are not copied') tells the agent what this tool will not do, which is useful guidance. However, there is no explicit statement of when to duplicate versus create a site, import a site, or pull a template, and no prerequisites (e.g., ownership of the source) are given.

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