browser_close

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

With no annotations provided, the description carries full responsibility for behavioral disclosure. 'Safely close' is vague and does not explain what the operation entails (e.g., whether it destroys the session, requires an active session, or is idempotent). No consequences or side effects are mentioned.

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, front-loaded sentence with no unnecessary words. Every word earns its place, making it maximally concise and easily scannable.

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 simple close operation with one optional parameter and no output schema, the description is minimally adequate. However, it lacks behavioral context (e.g., what happens if no session exists, whether it is safe to call multiple times) and does not clarify the meaning of 'safely', leaving gaps in the agent's understanding of edge cases.

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 schema provides 100% coverage for the single parameter (sessionId), including format and optionality, so the description need not add parameter details. The description itself adds nothing beyond the schema, but the baseline of 3 is appropriate given schema coverage.

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 verb 'close' and the resource 'browser session', making the tool's purpose unambiguous. It also distinguishes this tool from siblings like browser_launch and browser_connect, which start or attach to sessions.

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 guidance on when to use this tool versus alternatives, nor does it mention prerequisites or exclusions. The optionality of sessionId is only conveyed through the schema, not the description, leaving the agent without explicit 'when' or 'when-not' context.

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