new_tab

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

With no annotations provided, the description carries the full burden of explaining behavior. It clearly discloses that a new tab is opened, that navigation is optional, that the tab becomes active, and that the updated tab list is returned. This is meaningful transparency for a simple tab-creation operation.

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, tightly written sentence that front-loads the core action, adds the key optional behavior, and notes the return value. Every clause earns its place with no redundancy.

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 low complexity, one optional parameter, and absence of an output schema, the description covers the essential behavior and return value. It is somewhat light on parameter detail and alternative routing, but it provides enough for an agent to call this tool correctly in most cases.

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 single url parameter has no schema-level description, so the description's mention of 'optionally navigating to a URL' adds useful context by indicating the parameter is optional and controls navigation. It does not specify URL formatting or what happens when omitted, but the parameter name and string type make the basic meaning clear.

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 and resource: open a new tab, optionally navigate it to a URL, and make it active. This clearly distinguishes it from sibling tools like navigate, switch_tab, or close_tab by focusing on creating a new tab rather than operating on an existing one.

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 intended use is implied by the description: use this when a new tab should be created and activated. However, it does not explicitly contrast with alternatives such as navigate (for changing the current tab) or switch_tab (for activating an already-open tab), leaving some routing to inference.

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