check_auth

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, so the description is not burdened with baseline safety disclosure. It does add one useful behavioral detail—that this is a live check against the current-user API rather than a purely local read—but it doesn't say what happens on failure or what the response contains.

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?

A single front-loaded sentence with no filler; every word contributes to identifying the action, the object, and the live nature of the check.

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 parameterless read-only tool this is almost sufficient, but the absence of an output schema and the presence of several closely related auth-status siblings leave the agent without guidance on what the verification result looks like or when to prefer this tool over get_login_status, check_mytu_auth, or check_mail_auth.

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?

The tool has zero parameters, so per the calibration baseline it scores 4; there is no parameter information for the description to add beyond the empty schema.

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 a specific verb ('Verify') and a clear resource ('the saved session against the live current-user API'), so an agent knows what action to take. It does not explicitly distinguish this from sibling auth-status tools like get_login_status, check_mytu_auth, or check_mail_auth, so it stops short of a 5.

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 wording implies the use case: when you need to confirm that a saved session is still valid by checking the live current-user API. However, it gives no exclusions and names no alternative tools, so an agent selecting among the many auth-check siblings has to infer when check_auth is the right choice.

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