browser_new_tab

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 mentions that the new tab is made active, which is a useful behavioral trait, but it does not disclose side effects (e.g., what happens if the URL is invalid, whether the tab is created in the background, or what the return value is). For a tool with zero annotation coverage, this is insufficient.

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, clear sentence with no filler. It conveys the action, the optional parameter, and the resulting state (active) efficiently. Every word earns its place.

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 simple tool with one optional parameter, the description is mostly complete. It covers the core operation and the active-state behavior. It does not describe the return value or potential error conditions, but given the tool's simplicity and lack of an output schema, these are minor omissions. An agent can correctly call it with just this description.

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 has a single optional url parameter with no description, so the description's phrase 'optionally at a URL' adds meaning by indicating that the url parameter sets the new tab's address. While the schema already marks it as optional, the description clarifies its role, which compensates for the 0% schema coverage.

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 action (open a new tab) and the resource (tab), and adds the behavior of making it active. It distinguishes from list/select/close but does not explicitly contrast with browser_navigate, which also manipulates tabs. Still, the purpose is unambiguous.

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?

There is no guidance on when to use this tool versus alternatives like browser_navigate or browser_select_tab. The 'optionally at a URL' hints at flexibility but does not explain scenarios where a new tab is preferable to reusing an existing one. No exclusions or alternative recommendations are given.

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