browser_close_tab

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

No annotations are provided, so the description must disclose behavioral traits on its own. It only states the action without mentioning what happens if it's the last tab, whether it requires an active connection, or any side effects like losing unsaved state. This lack of behavioral detail 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 short sentence that directly states the action. Every word earns its place; there is no redundant information.

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 (zero parameters, no output schema), the description covers the basic action, but it omits important contextual behavior such as handling the last tab or connection requirements. For a tool this simple, the basics are present but edge cases are unexplored, making it adequate yet not fully complete.

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 schema is entirely self-explanatory. The baseline score for no-parameter tools is 4, and the description adds no unnecessary parameter information.

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 uses a specific verb ('close') and resource ('tab'), clearly distinguishing it from sibling tools like browser_new_tab, browser_list_tabs, and browser_switch_tab which perform different operations. It is unambiguous about the action performed.

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 tool's purpose is self-evident; there are no sibling tools for closing a tab, so no exclusions are needed. However, it doesn't explicitly state when to use it (e.g., before navigating away), but the context is clear and there are no competing alternatives.

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