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

The description adds the behavioral context of freeing resources, which is beyond the annotations (readOnlyHint: false). It confirms the destructive nature of the tool without contradicting annotations.

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 redundant words. Every part adds value: action, resource, and effect.

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?

Given the tool has no parameters, no output schema, and annotations are present, the description sufficiently covers the tool's purpose and effect. No additional context is necessary.

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?

With no parameters, the schema coverage is vacuously 100%. Per baseline rules for 0-parameter tools, a score of 4 is appropriate since no additional parameter information is needed.

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' and the resource 'underlying browser', with the effect of freeing resources. It effectively distinguishes this cleanup tool from sibling Playwright interaction tools like navigate or click.

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 as a cleanup step after browser interactions, but the description does not explicitly state when to use it (e.g., 'after finishing browser tasks') or when not to use it. Lacks explicit guidance on context.

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