browser_tabs

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

No annotations are provided, so the description carries full burden. It mentions actions but lacks behavioral details: it doesn't specify permissions needed, side effects (e.g., closing tabs is destructive), rate limits, or what 'focus' entails (e.g., brings tab to foreground). For a multi-action tool with no annotation coverage, this leaves significant gaps in understanding how it behaves.

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 extremely concise and front-loaded, stating the core purpose in a single, efficient sentence. Every word earns its place, with no redundant or vague phrasing. It effectively communicates the tool's scope without unnecessary elaboration.

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 tool's complexity (multiple actions with different behaviors) and lack of annotations or output schema, the description is incomplete. It doesn't explain return values, error conditions, or behavioral nuances (e.g., what 'list' returns, how 'focus' works). For a tool with no structured support, more context is needed to guide effective use.

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%, so the schema already documents all parameters (action, tabId, url) with descriptions and enum values. The description adds no additional parameter semantics beyond implying that actions map to parameters (e.g., 'create' uses url, 'close/focus' use tabId). This meets the baseline of 3 when schema does the heavy lifting.

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 states the tool's purpose with specific verbs (list, create, close, focus) and resource (browser tabs), making it immediately understandable. It distinguishes from siblings by focusing on tab management rather than navigation, interaction, or content extraction. However, it doesn't explicitly differentiate from all siblings (e.g., browser_navigate also deals with tabs).

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, appropriate contexts, or comparisons with sibling tools like browser_navigate (which might handle tab navigation differently). The agent must infer usage solely from the action list without explicit direction.

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