List who a site is shared with

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

Annotations already declare readOnlyHint=true, so safety is covered, but the description adds real behavioral context beyond them: the two possible permission values (`view`/`comment`), whether each person has opened the site, and the subtle conditional that the list governs access only while the site is invite-only. That last point is non-obvious domain behavior an agent could not infer from structured fields.

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 compact sentences, front-loaded with what is listed and followed by the returned attributes and the conditional permission nuance. Dense but every clause carries information; the second sentence's nested clause is slightly packed but earns its place.

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, the description needn't explain return shapes, yet it still characterizes the returned data well, and readOnlyHint covers safety. For a single-parameter read tool this is nearly complete; only error/permission-failure behavior is left unstated, a minor gap.

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% and the lone `site` parameter is fully documented in the schema (subdomain or id, sourced from list_sites). The description adds no additional syntax or format detail beyond scoping the parameter to 'a site's list', so the baseline 3 for schema-driven params is appropriate.

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 — listing the people on a site's invite list — and ties that list explicitly to whoever 'invite_people added', which distinguishes it from unrelated siblings like list_comments or list_sites. It also names the returned fields (permission level, opened-yet flag), so an agent knows exactly what this retrieves.

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 description gives clear context on which list is being read (the invite list, not general site membership) and references the sibling invite_people that populates it, implicitly routing the agent. It stops short of explicit when-to-use vs. when-not guidance or naming alternatives like get_site or remove_person.

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