browser_close

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

With no annotations, the description carries the full burden. It discloses the action, the conditional 'if open', and the return type (confirmation message). It doesn't detail edge cases like behavior when browser is already closed, but 'if it's open' implies idempotency. This is adequate for a simple close 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 extremely concise: three short sentences plus a returns line. The main action is front-loaded, and every sentence adds value. No unnecessary details.

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 tool with no parameters and an output schema, the description is complete. It covers what it does, when to use it, and what it returns. The low complexity means nothing is missing for an agent to call it correctly.

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 the schema trivially covers all. The description doesn't need to explain parameters. Baseline for 0 params is 4; no additional info is required.

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 action: close the persistent browser. It specifies the resource (persistent browser) and condition (if open), which is distinct from sibling tools like browser_keep_open and browser_status. The purpose is unambiguous.

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 provides explicit context: use when done with authentication operations and only when persistence is enabled. It references browser_keep_open to clarify the condition. It doesn't compare with session_browser_close, but the guidance is clear enough for selection.

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