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

Goes well beyond the annotations: it discloses that cookies are preserved and the browser 'sleeps' (state is not destroyed, consistent with destructiveHint=false), that the per-minute billing stops, and what the response reports. Cost and state-retention details are exactly the operational context annotations cannot convey.

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?

A single compact sentence with the action front-loaded, followed by the state and billing consequences and the return value. No redundant restatement of the title or annotations.

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?

With no parameters, no output schema, and simple semantics, the description covers everything an agent needs: the trigger, the state outcome, the billing effect, and the shape of the response (minutes and credits). Nothing material is missing.

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?

There are zero parameters, so there is nothing for the description to disambiguate; the baseline applies. It correctly implies no inputs are needed to close the session.

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 ('Ends the browser session') and names the triggering condition ('when the task is done'), which cleanly separates it from the sibling cotlet_browser_open and the other browser_* action 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?

Gives a clear usage condition ('when the task is done'), which is enough to select it over the browser_* interaction tools. It does not explicitly say when NOT to close (e.g. mid-workflow with pending state) or name cotlet_browser_open as the counterpart, so it falls short of full when/when-not guidance.

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