Browser Session Close

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

With no annotations provided, the description carries the full burden. It discloses the destructive side effect (cookies/storage discarded) and the exception (unless saved). This is valuable beyond the schema. It does not mention reversibility or permissions, but the primary behavioral trait is covered.

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 states the primary action, followed by a parenthetical that adds essential behavioral context. No wasted words; it is clear and compact.

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?

Given the tool's simplicity (one parameter, output schema present), the description is mostly complete. It covers the key side effect. It does not describe error conditions or what the output contains, but since an output schema exists, that is less critical. The missing parameter explanation is a gap, but the overall context is adequate.

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 0% and the description does not explain the 'name' parameter. The agent must infer that 'name' refers to the session identifier. The description only says 'Close a session' without connecting it to the parameter, so it fails to compensate for the missing schema documentation.

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 clearly states the action: 'Close a session and all its tabs.' It specifies the resource (session) and scope (all its tabs), which distinguishes it from browser_tab_close that closes a single tab. The cookie/storage note further clarifies behavior.

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 description implies this is for closing an entire session but does not explicitly compare to alternatives like browser_tab_close. It does mention the prerequisite of saving auth with browser_session_save_auth to preserve cookies/storage, offering some contextual guidance, but no explicit 'use this when' or 'don't use this when'.

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