focus_tab

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

The description discloses the concrete behavior—bringing a tab to the front and activating it—which goes beyond the abstract annotations (idempotentHint, destructiveHint). But it does not mention failure behavior for invalid tab IDs or any prerequisites such as the tab being in the same window, leaving some behavioral gaps.

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 11-word sentence that front-loads the action and includes no filler. Every word contributes to the meaning.

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 tool with one required parameter, a fully described schema, and no output schema, the information provided is sufficient for an agent to invoke it correctly. The sibling tool list_tabs implies where tab IDs come from, completing the context.

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 input schema already provides 100% coverage: tabId is a number described as 'The ID of the tab to focus'. The description adds no additional detail about the parameter itself, so the baseline score of 3 is appropriate.

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 verb ('Bring'), a resource ('a specific browser tab'), and the outcome ('to the front and make it active'). This clearly distinguishes it from sibling tools like open_tab (creating/opening a new tab) and close_tab/reload_tab.

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?

Usage is implied: you use this when you have an existing tab ID and want to bring that tab to the foreground. However, there is no explicit guidance about when not to use it or which alternative to choose (e.g., open_tab for new tabs), so the agent must infer the appropriate context.

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