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

The description says the tool "clears the stored token," which is a state mutation, while annotations declare readOnlyHint: true (does not modify its environment). The description is arguably the accurate side here, but as written it directly conflicts with the structured safety profile an agent relies on. It also says nothing about whether the session is invalidated server-side or what happens on repeat calls.

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?

One front-loaded sentence with the effect in a parenthetical — zero waste, no repetition of the title, and the key consequence is stated up front.

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 parameters, an output schema present, and a small set of annotations, the description covers the essentials of what the tool does. It leaves open how this relates to auth_status (the natural companion for verifying state) and whether the sign-out is local-only or also server-side.

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 the baseline is 4; there is nothing parameter-level the description needs to compensate for and schema coverage is 100%.

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?

"Sign the customer out of this session" names a specific verb and scope, and the parenthetical clarifies the concrete effect (token cleared). It is clearly distinguishable from read-only siblings such as auth_status or get_profile, though it never names those siblings explicitly.

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 phrase "of this session" scopes the action, but there is no explicit when-to-use guidance (e.g., "call when the customer requests sign-out; use auth_status to check current state first"). Usage is implied by the self-evident name rather than stated.

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