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 burden of behavioral disclosure. It adds one important behavior: session ownership limits which tabs can be closed. However, it does not mention what happens on success or failure, whether closing is irreversible, or whether the tab's resources are also released. For a destructive action, some additional context would be valuable.

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?

Two short sentences with no filler. The core action is front-loaded, and the session ownership limitation is stated as a separate, important constraint. 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?

This is a simple single-parameter tool with no output schema. The description covers what the tool does and the key limitation an agent must respect. It is mostly complete for a focused close operation, though it could briefly note what happens when the tab ID is invalid or stale.

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 description coverage is 100%, and the tab_id parameter is already described clearly as 'Tab ID to close (get from browser_list_tabs)'. The description reinforces the parameter's role but does not add significant meaning beyond the schema. Baseline 3 applies.

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 states a specific action ('Close'), a specific resource ('a browser tab'), and the method ('by ID'). It clearly distinguishes this tool from siblings like browser_switch_tab and browser_list_tabs, so an agent can immediately understand its role.

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 makes the tool's purpose obvious: call it when a specific tab should be closed. It also provides a meaningful constraint: only tabs owned by the current session can be closed. It does not explicitly name alternatives or describe when not to use it, but the narrow scope makes the usage context clear.

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