close-browser

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

No annotations are provided, so the description must disclose behavioral implications. It does not mention side effects of closing (e.g., whether open tabs are lost, whether the process is terminated, whether it is reversible), nor does it state what happens if the contextId is invalid. For a mutating operation, this is a significant gap.

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 efficient sentence with no filler words. It clearly communicates the action and target without redundancy or unnecessary detail.

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 one-parameter tool, the description is minimally adequate. However, because there is no output schema and no annotations, it does not explain how to discover contextId, whether the operation returns a value, or how errors are handled. This leaves an agent without enough context for fully reliable invocation.

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 covers the only parameter, contextId, with the description 'ID of the browser to close,' giving 100% schema coverage. The tool description does not add additional meaning beyond the schema, so the baseline 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 uses a clear verb and resource: 'Closes a specific browser instance.' This distinguishes it from siblings like start-browser and list-browsers by naming the action and target. It could be slightly improved by noting that the instance is identified via contextId, but the core 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?

No guidance is given on when to use this tool versus alternatives like start-browser or list-browsers, nor is there any mention of how to obtain contextId. The description implies usage only at the most basic level ('close something'), without context or exclusions.

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