Auth Status

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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world, so the safety profile is covered. The description adds real value beyond that by disclosing the return payload shape, including auth method enumeration and token expiry, which tells the agent this is a safe informational probe rather than a check that refreshes credentials.

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, both earning their place: the first front-loads trigger phrases, the second enumerates return values. No repetition of the title or 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 and no parameters, the description carries the burden of describing the response, and it does so completely by naming all four returned facts. An agent has everything needed to select and call it correctly.

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, which is the baseline-4 case; there is nothing for the description to disambiguate. The description correctly implies no inputs are needed by framing it purely around user questions.

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?

States a specific resource (server auth state) and enumerates exactly what is returned: authenticated flag, linked account, method (API key/JWT/device auth), and token expiry. This clearly distinguishes it from auth_login and auth_logout in the sibling list, which mutate auth state.

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?

Provides four concrete user phrasings that should trigger this tool ('am I logged in', 'which account', 'how am I authenticated', 'when does my token expire'), giving strong positive routing. It does not explicitly name auth_login/auth_logout as the alternatives to avoid, but the read-only framing makes the boundary reasonably clear.

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