close_browser

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

Annotations declare this a non-read-only, open-world, non-destructive operation; the description adds the meaningful context that persistent profiles survive, so the agent knows closing does not wipe stored identity/session state. It stops short of describing whether in-memory state is discarded or what the output contains, but the key data-loss question is answered.

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 the important caveat parenthesized immediately after. No filler.

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 parameterless teardown tool with annotations and an output schema, the description covers the essential fact (profiles persist) and the resource outcome. Only marginal additions -- behavior of active tabs or in-flight steps after close -- are 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?

The tool takes zero parameters, so there is nothing for the description to disambiguate; baseline applies. No misleading hints about arguments are given.

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') plus the side effect ('free resources'), which is distinct from the tab-level sibling tab_close. It does not explicitly name that sibling as different, so the differentiation is implied by the resource scope rather than stated.

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?

Usage is implied (teardown / end of session) but never stated, and there is no guidance on when to use tab_close instead of closing the whole browser, nor on when closing would be inappropriate (e.g. mid-run_steps). An agent must infer the call conditions.

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