close_active_tab

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

With no annotations provided, the description carries the behavioral disclosure burden. It clearly reveals the destructive side effect (the currently active tab will be closed), and there are no parameters or auth/rate-limit concerns to disclose. It does not mention edge cases like closing the last tab or browser focus changes, but the core behavior is unambiguous.

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 entire description is one short, front-loaded sentence that says exactly what the tool does. There is no filler, no repetition, and no unnecessary content.

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?

This is a simple zero-argument destructive action with an output schema available. The description states the target and the action sufficiently, and with no parameters, the agent has everything needed to invoke it correctly.

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 has zero parameters and the schema already provides complete coverage, so there is nothing for the description to add. A score of 4 is the baseline for a parameterless tool.

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 identifies the resource ('currently active tab'), which clearly distinguishes it from sibling tools like close_browser, switch_to_tab, or open_new_tab. It tells an agent exactly what action is taken and on what.

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 intended use is implicit: call this tool when the current active tab should be closed. However, the description gives no explicit when-to-use or when-not-to-use guidance, nor does it mention alternatives such as close_browser for ending the whole browser session.

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