Close browsers

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

Annotations already provide idempotentHint=true and destructiveHint=false. The description adds the 'by profile UUID' scoping, which is useful, but it does not go beyond that to describe error behavior, effects on profile data, or what happens when a browser is not running. Given the annotations, this is adequate but not exceptional.

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 sentence with no filler, effectively conveying the tool's purpose in minimal words. It earns every character and is well structured.

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 one-parameter tool with clear annotations (idempotent, non-destructive). The description explains what it does and the schema covers the parameter. Minor gaps like error handling or behavior for missing UUIDs are not critical, but a slightly more detailed description could have noted that closing is a no-op for non-running browsers, though that is implied by idempotentHint.

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 input schema fully describes the single parameter 'profile_uuids' as 'Profile UUIDs to close', and the description echoes 'by profile UUID'. No additional semantic value is added beyond what the schema already provides, so the baseline score of 3 is appropriate.

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 resource (running browsers), and the identifying key (profile UUID). It effectively distinguishes this from siblings like open_browser and list_running_browsers by specifying both the operation and its scope.

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 phrase 'running browsers' implies that this tool is for browsers already open, and that one might first use list_running_browsers to get UUIDs. However, the description does not explicitly mention when to use this tool versus alternatives, nor does it note any exclusions or prerequisites.

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