close_browser

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

With no annotations, the description carries the full burden, and it delivers. It discloses that closing ends persistent browser state, enumerates the destroyed state (tabs, cookies, navigation history, page state), and explicitly states it is safe to call when no session is active. This is strong behavioral disclosure for a teardown operation.

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 compact and well-structured: an immediate behavioral statement, a clear usage condition, the side-effect disclosure, and the fallback action. Each sentence earns its place and the most important information is front-loaded.

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 tool is simple (zero parameters) and has an output schema, so the description need not explain return values. It fully covers what the tool does, when to use it, what state it destroys, and how it behaves in an edge case. Nothing needed for correct invocation 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?

The tool has zero parameters and the schema documents them trivially with 100% coverage. Since there are no parameters to describe, the baseline of 4 applies; the description appropriately spends no space on parameter semantics.

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 states a clear verb-resource pair: 'Close the active browser session and release browser resources.' It is specific about the scope (the active session) and naturally distinguishes itself from the sibling start_browser without ambiguity.

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?

It explicitly says when to call this tool: 'when the browser automation workflow is finished.' It also names the alternative for follow-up work: 'start a new session with start_browser.' It additionally clarifies the safe no-op case, leaving no doubt about when invocation is appropriate.

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