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

With no annotations, the description carries the transparency burden. It discloses the email side effects (new accounts get a confirmation link, established accounts get a sign-in URL) and clarifies password-reset behavior (only the account holder's mailbox gets the reset link). It does not cover failure modes or permissions, but for a simple resend action the core behavior is visible.

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?

The purpose is front-loaded in the opening sentence and the additional sentences earn their place by explaining email outcomes and the reset-link behavior. The phrase 'Check emailed' is slightly cryptic and the reset detail is tangential, so it is not perfectly polished.

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 low-complexity two-parameter tool, the description explains what happens on success and offers a practical fallback check. However, with no output schema or annotations, it omits return/error behavior and the prerequisite that the person must already have an invitation, leaving some ambiguity for an agent.

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 description coverage is 100%, and the description adds nothing about the email or workspace parameter beyond what the schema already documents. It refers to 'someone in the workspace' but supplies no new syntax, constraints, or format guidance, so 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 first sentence is a precise verb-resource statement: 'Resend an invitation to someone in the workspace.' This distinguishes it from users_add (initial invite) and users_remove, though it never names those siblings and does not explicitly state that it is not for first-time invites.

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 practical context: new vs established accounts and a directive to 'Check emailed before offering a fallback.' It implies when the tool is appropriate but does not explicitly state when to use it instead of users_add or how to handle an uninvited email.

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