Close browser session

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

The annotations already declare destructiveHint=true and idempotentHint=true, so the description doesn't need to reiterate that. However, it adds value by specifying the dual behavior: closing the browser entirely or detaching tabs in attach mode. This goes beyond what annotations convey, but the description could mention that open pages or state will be lost if tabs are closed.

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 a single sentence that is concise and front-loaded, clearly stating the action without any filler. Every word earns its place.

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 that the tool has 0 parameters, an output schema exists, and the annotations are rich (readOnlyHint, openWorldHint, idempotentHint, destructiveHint), the description is mostly sufficient. It explains the core behavior but misses minor behavioral details such as error handling or what happens if no session is active.

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?

There are zero parameters, and the schema description coverage is 100%, so the schema provides all necessary information. The description adds no parameter info, but no compensation is needed. With 0 params, the baseline is 4, and the description is adequate.

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 that the tool closes the browser session or detaches tabs in attach mode, using a specific verb ('Close') and resource ('managed browser' or 'MCP-owned tabs'), and it distinguishes itself from sibling tools like browser_open, browser_snapshot, and browser_query, which perform different operations.

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 that the tool should be used when you want to end a browser session or detach tabs, but it does not explicitly state when not to use it or what alternatives (e.g., leaving the browser open) exist. The context of sibling tools is provided but not leveraged in the description.

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