browser_close_tab

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions the default behavior (active tab) but does not disclose potential side effects such as unsaved data loss, confirmation dialogs, or error behavior when tabId is invalid. For a destructive action, this is a significant gap.

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, front-loaded sentence with no unnecessary words. It states the action, the parameter, and the default in a compact and efficient manner.

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 simple tab-close operation, the description is functional but minimal. It lacks information about return values (no output schema), error handling, or side effects. Given the lack of annotations, the description should provide more context to ensure correct invocation, especially for a destructive operation.

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 schema has one parameter (tabId) with no description (coverage 0%), so the description must compensate. It explains that omitting tabId defaults to the active tab, adding meaning beyond the schema. However, it does not explain what the id represents (e.g., how to obtain it) or any constraints on its value.

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) and the resource (a tab), with the parameter being the tab id and the default being the active tab. It is distinct from sibling tools like browser_list_tabs or browser_select_tab, though it doesn't explicitly name alternatives. The purpose is unambiguous.

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?

There is no guidance on when to use this tool versus alternatives like browser_select_tab or browser_new_tab. The description only states what it does, not the context or conditions for its use. No exclusions or preferred scenarios are mentioned.

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