close_browser

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

No annotations are provided, so the description carries the behavioral disclosure burden. It does disclose that cookies persist on disk after closing, which is meaningful behavioral context beyond just 'close browser'. However, it doesn't explain what state is lost (open tabs, in-memory data) or whether subsequent tool calls require a new context or login.

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, compact sentence with no waste. The parenthetical adds genuine value without bloating the description. 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?

This is a simple zero-parameter tool with no output schema, so the description burden is minimal. It covers the primary action and the notable side-effect (cookie persistence). The main gap is not explaining follow-on state: whether a new login/navigation is required after closing, or whether certain tools become unusable until reopened.

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 has zero parameters, so there's nothing for the description to explain about parameters. With schema coverage at 100% and no params to describe, a baseline 4 is appropriate since there's no parameter ambiguity needing resolution.

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 tool closes the Playwright browser context, with a specific verb (close) and resource (browser context). It also adds a useful clarification about session cookies remaining on disk, distinguishing the effect from full session deletion. This clearly distinguishes it from tools like linkedin_logout.

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?

The description gives no explicit when-to-use or when-not-to-use guidance. The parenthetical about cookies remaining on disk implies a limited scope of what closing does, but there's no mention of when closing is appropriate vs alternatives, or any cleanup implications. Usage context is implied rather than explicit.

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