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

Annotations already declare readOnlyHint and destructiveHint=false, yet the description still adds real value: the required key scopes (deploy:write or sites:read), the hard limit of 3 subdomain changes per month, and the notion of a stopped state with suspended/hold_kinds. 'Read-only; changes nothing' merely restates the annotations, but the scope and limit details go beyond them.

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?

It is a single dense sentence with the safety statement front-loaded and the returned fields listed in order. The parenthetical scope and limit asides are efficient, though the telegraphic style ('suspended, hold_kinds') makes it slightly harder to parse than necessary.

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 carries the burden of describing return content, and it does enumerate the fields an agent will get back. Combined with the auth scopes and the monthly limit, an agent has enough to call it correctly; only the relationship to sibling hosting tools is left unstated.

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?

There is a single parameter with 100% schema description coverage, and the schema already explains that 'site' is the id from list_sites (e.g. "my-shop"). The description adds no format or sourcing detail beyond that, so the baseline 3 applies.

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 enumerates exactly what the tool reports about a site's hosting: serving state, subdomain and URL, live version, monthly subdomain-change usage, and suspension state. That is specific enough for an agent to recognize it as a hosting status read. It stops short of naming the sibling it differs from (hosting_subdomain), so it lands at 4 rather than 5.

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?

Usage is only implied: an agent can infer it should call this to inspect hosting before deploying or changing a subdomain, but the description never states when to use it, when not to, or how it relates to hosting_subdomain or fetch_site. The scope note (deploy:write or sites:read) is authorization context, not selection guidance.

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