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

Annotations already declare readOnlyHint=false, destructiveHint=false, and idempotentHint=false, so the safety and repeat-call profile is covered. The description's real addition is the return payload (id, editor link, previewUrl), valuable since no output schema exists, but it says nothing about slug uniqueness, template validity, permission requirements, or failure modes.

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 zero waste: the action and its output are front-loaded, and the follow-up workflow hint comes second. Nothing is repeated from the schema or annotations.

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?

For a zero-required-parameter creation tool with no output schema, the description covers the action, the default, the returned fields, and the next step. It could be more complete by pointing at list_templates for discovering non-default template slugs or by noting that the site is unpublished until publish_site.

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 all four parameters are already documented and baseline would be 3. The description earns a bump by explaining that the default template "acme" is the blank starter, which gives semantic meaning beyond the schema's bare "Template slug (default \"acme\")".

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 and resource ("Create a site from a template") and adds scope detail (default "acme", the blank starter) plus what is returned. It does not explicitly differentiate itself from close siblings like duplicate_site, import_site, or pull_template, so an agent must infer which creation path applies.

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?

"Then build it with the file tools" gives useful next-step routing to write_site_file/edit_site_file, so the workflow position is implied. However, there is no when-not guidance and no statement about choosing this over import_site, duplicate_site, or list_templates first.

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