browser_close

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

With no annotations provided, the description carries the full burden of disclosure, and it only restates the action. It does not say what is destroyed (open tabs, session/cookies, in-flight downloads), whether the call is idempotent or errors when no browser is running, or what the response contains. For a terminal/cleanup action, these are meaningful gaps.

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 short sentence with the action front-loaded and zero filler. It is arguably too terse for a state-destroying operation, but nothing is wasted.

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?

The schema and annotation structures contribute nothing here (no params, no annotations, no output schema), so the description is the only information source and it explains only the action. It omits lifecycle preconditions, effect on session state, and failure modes, which an agent needs to sequence this against browser_launch and the other browser_* calls.

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 there is nothing for the description to disambiguate and the baseline of 4 applies. No parameter text is needed.

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 ("Close the browser") in a form that is unambiguous. Because browsers in this toolset are launched with browser_launch, an agent can infer the pairing without opening the schema. It stops short of the sibling differentiation in the highest band, which would explicitly name the launch/close lifecycle.

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 guidance on when to call this versus leaving the browser open, no mention of prerequisites (must a browser be launched first?), and no warning that closing may invalidate page state needed by other browser_* tools. The agent must infer all of this.

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