登出網頁聊天服務（不開瀏覽器視窗）

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

With no annotations, the description carries the full burden and does so well. It discloses the exact mechanism (clearing cookies), the headless no-window context, the side effect of clearing google.com cookies when logging out of gemini, the re-check of login state, and that guest use remains functional. This is rich behavioral context beyond what structured fields provide.

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?

The description is front-loaded with the core action and mechanism, followed by targeted additional details about gemini, webchat_login, and guest use. Every sentence adds useful context, and there is no unnecessary filler despite slight redundancy between 'headless' and 'no window shown'.

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 one-parameter logout tool with no annotations and no output schema, the description is nearly complete: it explains the mechanism, side effects, re-login path, and guest behavior. The main remaining gap is that it does not describe what the tool returns or how the re-checked login state is surfaced, which is more relevant given the absence of an output schema.

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 coverage is 100%, so the enum values and default are fully documented in the schema. The description still adds provider-specific meaning by explaining that logging out of gemini clears google.com cookies and signs the profile out of Google, which is relevant to interpreting the provider parameter.

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 verb (log out) and resource (chosen web chat service), plus the mechanism (clearing cookies from the built-in browser profile). It distinguishes from webchat_login explicitly, but does not differentiate from other siblings like webchat_release or webchat_close, so it falls just 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?

Usage is implied: log out to clear cookies, then use webchat_login to log in again. It also notes guest use continues. However, there is no explicit when-to-use vs when-not-to-use guidance, nor comparison to alternative logout-related siblings such as webchat_release or webchat_close.

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