Manage tabs

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

The description names destructive behavior (closing tabs) and clarifies default behavior for closing without an index. It does not contradict the annotations, and it carries the transparency burden since readOnlyHint and destructiveHint are both false.

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 compact two-sentence summary that states the core operations and a key preference rule. No filler or redundant phrasing 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?

The description covers invocation and behavior for the main actions, but it does not describe the return value or output format for actions like list or create. Since there is no output schema, this missing information leaves some ambiguity for an agent.

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 schema descriptions cover all parameters, and the tool description adds decision logic about preferring select over new. The action parameter description is somewhat generic ('Operation to perform'), but the enum values are self-explanatory and reinforced by the tool description.

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 primary actions—list, create, close, or select—and the resource is a browser tab. It is unambiguous and distinguishes itself from sibling navigation and page-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 actionable guidance: 'Prefer select over new when a matching tab already exists.' This helps an agent decide between the select and new actions, though it does not explicitly enumerate all sibling alternatives.

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