login_status

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

With no annotations supplied, the description carries the full burden and does add real behavioral context: it scopes the return to QR path plus session status, warns that saved state can expire, and states a security constraint that browser credentials are never returned. It still omits whether the call requires an existing session or what status values can appear.

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 tight sentences, each doing work: the first defines the return scope and the second supplies the expiry caveat and the credential-safety guarantee. Nothing is padded or buried.

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 zero-parameter, no-annotation tool with no output schema, the description covers purpose, return scope, and the key operational caveat. It is slightly incomplete in not enumerating possible session statuses or linking back to start_login, but nothing critical to invoking it is missing.

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 takes zero parameters, so per the rubric the baseline is 4; there is nothing for the description to clarify beyond the schema's empty argument object.

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 ('Return') and precise resources ('QR path and dedicated-session status'), so an agent knows this is a read-only status probe rather than an action tool. It does not explicitly distinguish itself from the closely related sibling start_login, which weakens differentiation.

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 caveat 'Saved state can expire' implies the tool should be re-invoked to refresh a stale login session, but there is no explicit when-to-use statement or comparison to start_login. Usage is inferable but not spelled out.

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