list_tabs

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the action ('List') but doesn't describe what 'active tabs' means, the return format (e.g., list of tab IDs or URLs), or any side effects (e.g., if it refreshes tab data). For a tool with zero annotation coverage, this leaves significant gaps in understanding its 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 is a single, efficient sentence ('List all active tabs') with zero wasted words. It's front-loaded with the core action and resource, making it immediately scannable and easy to understand. Every word earns its place by directly contributing to the tool's purpose.

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 complexity (a read operation with no parameters) and lack of annotations or output schema, the description is incomplete. It doesn't explain what 'active tabs' entails, the return format, or how it interacts with the browser context. For a tool in a browser automation suite, more context is needed to use it effectively alongside siblings.

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 0 parameters, and the input schema has 100% description coverage (though empty). The description doesn't need to add parameter semantics, as there are none to explain. It appropriately focuses on the tool's purpose without unnecessary parameter details, meeting the baseline for zero-parameter tools.

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 'List all active tabs' clearly states the verb ('List') and resource ('active tabs'), making the purpose immediately understandable. It distinguishes from siblings like 'close_tab', 'create_tab', and 'set_active_tab' by focusing on listing rather than modifying. However, it doesn't specify the scope (e.g., current browser window vs. all windows), which prevents a perfect score.

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 no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an active browser session), exclusions (e.g., not listing inactive tabs), or related tools like 'get_current_url' for tab details. Without any usage context, the agent must infer when this tool is appropriate.

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