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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered structurally. The description adds real context beyond that: the owners/admins authorization requirement and the fact that only pending, unexpired invitations are returned. It says nothing about ordering, pagination, or empty-result behavior, so it is good but not rich.

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 what is listed and immediately followed by the authorization gate and next-step pointer. Every sentence carries information, with no 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 single-parameter read tool with no output schema, the description covers the return fields inline (id, email, role, expires_at), the permission requirement, and the downstream tool. An agent has everything needed to invoke and interpret it.

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 one parameter with 100% schema coverage, and the schema already tells the agent to get workspace_id from list_workspaces. The description adds no syntax or format 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 names a specific verb and resource ('Lists ... email invitations to join a workspace') and narrows the scope to pending, unexpired invitations. It also enumerates returned fields, which clearly separates it from siblings like list_workspace_members and list_workspace_people.

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?

It states an explicit permission gate ('Owners and admins only') and points to the follow-up action ('Use the id with revoke_workspace_invitation'). It does not explicitly contrast with list_workspace_members/list_workspace_people, but the pending-invitation framing makes the boundary implicit.

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