window_close

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

Annotations already mark destructiveHint=true, and the description adds valuable extra behavior: after closing the window, the VM remains locked by the session and must be explicitly unlocked via vm_unlock. This is useful post-condition context not present in 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 sentence with no filler. It conveys the core action and the essential lifecycle caveat about vm_unlock in minimal words.

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 with a destructive annotation and no output schema, the description covers the action and the important lock-state implication. The parameter schema provides the source of the window_id. No critical context is missing.

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?

Schema description coverage is 100%, and the parameter description 'Window handle returned by window_list' is already in the schema. The tool description does not add additional parameter semantics beyond what the schema provides, so it meets the baseline.

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?

Description states the specific action ('Request that a selected window close') with the resource being a selected window, which matches the tool name and clearly distinguishes it from sibling window tools like window_list, window_focus, and window_capture.

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?

Provides clear contextual guidance about the VM session lock lifecycle, instructing to call vm_unlock when finished. While it does not name explicit alternatives, there are no alternative close tools among siblings, and the locking instruction gives practical when-to-use direction.

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