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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the description adds genuine extra context beyond them: the "Owner only" permission requirement, the newest-first ordering, and privacy behavior (email shown as first letter and domain). It does not describe pagination, which is a minor remaining gap for a list 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?

Two sentences, front-loaded with the permission constraint and scope before the when-to-use guidance. Dense but every clause carries information; no filler.

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 usefully describes the return shape (invite states, inviter/joiner info, masked email vs token). Combined with read-only annotations this is nearly complete; pagination behavior is the only notable omission.

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%; workspace_id and api_token are both fully documented in the schema, including that api_token can be omitted when the Authorization header is set. The description adds nothing about parameters, so the baseline 3 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?

The description names a specific resource and scope: "This workspace's invites, newest first," and enumerates the states returned (pending, joined, expired) plus delivery formats (email, token). This clearly distinguishes a read-listing operation from siblings like create_invite, invite_by_email and redeem_invite, though it never names those alternatives explicitly.

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 gives explicit intent: "Use it to see whether someone you invited joined, or whether their invite ran out and needs resending." This is real context for when to reach for the tool, but there are no stated exclusions or named alternative tools for adjacent needs.

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