browser_new_window

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

With no annotations, the description carries the full burden. It does disclose the return value ('Returns the new windowId'), which is valuable since there is no output schema, but it says nothing about side effects such as whether the new window takes focus, how incognito state persists, or whether hideWindow affects later calls.

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?

Two short sentences, front-loaded with the action and followed by the return value. Nothing is wasted and nothing important is buried.

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 three-optional-parameter tool with a fully documented schema, this is close to sufficient, and it correctly notes the returned windowId in the absence of an output schema. It stops short of clarifying the relationship to browser_new_tab and the window's focus/visibility behavior, which matter for correct invocation sequencing.

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% and all three parameters (url, incognito, hideWindow) are documented in the schema, so the baseline of 3 applies. The description adds no meaning beyond the schema, such as default visibility behavior or what happens when url is omitted.

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?

States a specific verb and resource ('Open a new browser window'), which is unambiguous on its own. It does not, however, distinguish itself from the close sibling browser_new_tab, so an agent must infer the window-vs-tab distinction.

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?

No when-to-use guidance and no mention of alternatives, despite a dense sibling set including browser_new_tab, browser_show, and browser_get_window_info. The agent gets no help choosing between opening a window and opening a tab.

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