browser_focus_tab

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

With no annotations provided, the description carries the full burden. It successfully discloses the tool's disabled status and side effects (window foregrounding), but omits error handling behavior (e.g., invalid tabId), effects on previously focused tabs, or timeout behavior.

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 consists of three efficient, front-loaded sentences. The '[Disabled]' prefix immediately signals availability, followed by the core action, use case, and prerequisite tool. No redundant or wasted language is present.

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 single-parameter schema and lack of output schema, the description adequately covers the essential operational context (disabled state, prerequisite tool, visual inspection use case). However, it lacks completeness regarding failure modes or edge cases (e.g., tab already focused, minimized window behavior).

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 coverage is 100%, establishing a baseline of 3. The description adds value by cross-referencing 'browser_list_tabs' to indicate how to obtain valid tabId values, but does not elaborate on the integer format constraints or validation beyond the schema.

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 defines the action ('Focus a browser tab'), the mechanism ('making it the active tab... bringing the window to the foreground'), and the current state ('[Disabled]'). It effectively distinguishes the 'focus' window-management behavior from sibling navigation or interaction tools.

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 provides an implied use case ('useful for... visual inspection') and explicitly references the prerequisite sibling tool 'browser_list_tabs' to obtain tab IDs. However, it lacks explicit 'when-not-to-use' guidance or alternatives for different goals (e.g., navigating vs. focusing).

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