browser_get_window_info

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

With no annotations, the description carries the full burden, and it does disclose the key ecosystem behavior: other tools operate on the frontmost window/tab by default, which reframes this tool as an opt-in orientation step. It stops short of saying whether the listing is cheap, whether popups/background windows are included, or what the exact return shape looks like.

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 sentences, zero waste: the first states what is listed and what identifiers come back, the second front-loads the decision guidance. Nothing redundant with the empty schema.

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 no-parameter, no-output-schema tool, the description covers both the content and the identifiers returned, which is the essential shape. Minor gap: without an output schema, it could say whether windows are ordered, whether popups/background windows appear, or how to act on the returned ids (e.g. select_tab).

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 tool takes zero parameters, so the baseline is 4. The description mentions windowId and tabId, but those are return values rather than inputs, so there is no parameter meaning left to add.

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?

Specific verb (list) plus resource (every browser window and its tabs) and it names the identifying fields returned (windowId, tabId). An agent can immediately tell this is a read-only enumeration of open windows, distinct from browser_status or browser_take_snapshot.

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?

Explicitly states the use case (find out what is open) and an explicit when-not: the other tools default to the frontmost window and tab, so you usually do not need to call this first. That routing guidance is exactly what an agent needs to avoid an unnecessary call.

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