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

With no annotations, the description must carry the behavioral burden. It usefully discloses the naming validation rules and that only { site } is returned (no deployment data), plus a prerequisite chain, but says nothing about authentication/permission requirements, behavior on name collision, or idempotency — notable gaps for a create/mutation tool.

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 short sentences, front-loaded with the core action and return shape, then validation, then prerequisites. No filler or redundancy.

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 one-parameter tool, the description covers what it does, the naming rules, the return payload, and the prerequisite ordering. It lacks permission/auth context and error semantics, which are the only meaningful omissions given the simple schema and absent annotations.

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 already 100% (the single "name" param is documented as a site slug), and the description adds real meaning on top: lowercase letters/digits/hyphens and a 1-64 character limit. That constraint detail is not in the schema, so it genuinely compensates beyond baseline.

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 new site") plus an ownership scope ("owned by the caller"), which distinguishes it from sibling operations like create_deploy_upload or list_sites without needing to open any 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 clear sequencing guidance: read server instructions and call get_deployment_rules before building a zip or deploying, positioning this as the first step of a deployment flow. It does not explicitly exclude alternatives or say when not to create a site (e.g., if one already exists), so it stops short of a full routing statement.

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