Mark a user as verified

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

With only idempotentHint=false in annotations, the description carries the behavioral burden and does add useful context: the normal user-click flow and the requirement of a confirmation token. It does not detail side effects like reversibility or notifications, but the key verification behavior is disclosed.

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 tightly scoped sentences with no filler. The main action is front-loaded, and the token requirement plus normal-flow context each earn their 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?

For a simple two-parameter mutation with full schema coverage, the description plus schema provide enough to invoke it correctly. It does not describe return values, but no output schema exists and the action's outcome is stated clearly.

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%, so the schema already documents user_id and confirm_token, including the important 'Omit it to receive one' behavior. The description adds no further parameter meaning beyond repeating the token requirement.

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 uses the specific verb 'Marks' and names the exact resource and outcome: 'an account’s email as verified.' This clearly differentiates it from sibling user-management mutations like update_user, set_user_active, or reset_user_password.

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 explains that verification is normally done by the user clicking a link, implying this tool is for manual/admin verification, and it highlights the confirmation-token requirement. It does not explicitly name alternatives or say when not to use it, but the context is clear for such a focused action.

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