tabs

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

With no annotations, the description carries the full burden and discloses rich behavior: closing the active tab returns to the opener else the newest, closing the last tab leaves a blank one, indexes shift after open/close, switching brings the tab to the front, and switching/closing asks for site permission with reason shown to the user. This covers side effects and permission flow thoroughly.

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?

Uses bullet points to organize the three actions and behavioral notes, front-loading the main purpose. Every sentence earns its place by covering index shifting, permission requests, or automatic tab handling without redundant filler.

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 multi-action tool with no annotations and an output schema, the description covers actions, index behavior, permission flow, and automatic following well. It neglects the confirm parameter and any error scenarios, but overall provides enough for an agent to call 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?

Schema description coverage is 0%, so the description must define parameters. It explains action values (list/switch/close), the meaning of index as a tab index, and the purpose of reason (shown to the user during permission prompts), but completely omits the confirm parameter, leaving one of four undocumented.

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?

States a specific verb and resource ('List the browser's tabs, switch to one, or close one') and enumerates the three actions with enough detail. An agent can tell this apart from siblings like open_browser, close_browser, and navigate without opening any schema.

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?

Provides clear context: list to see indexes, switch to activate a tab, close to remove it, and notes that automatic following handles most popups so this tool is for when you must choose manually. It lacks explicit alternatives (e.g., when to use navigate vs switch) but the usage context is well-defined.

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