vm_stop

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

With no annotations, the description carries the safety burden. It clearly discloses that soft asks the guest to shut down while hard cuts power, and that hard needs explicit confirmation. This is meaningful behavioral context, though it does not describe side effects like possible data loss from hard power-off or whether the call waits for shutdown completion.

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?

A single, compact sentence that front-loads the main operation and packs the mode distinction and confirmation requirement into minimal words. No filler or redundant restatement.

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 straightforward three-parameter tool with no output schema, the description provides enough context to invoke it correctly: the VM name comes from vms.yaml, mode is soft or hard, and confirm is required for hard. It does not explain return behavior, but that is not essential here.

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 coverage is 100%, so the baseline is 3. The description adds value by explicitly tying confirm=true to hard mode, a relationship the schema only implies through separate field descriptions. This helps an agent understand how the parameters interact.

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 specific verb ('Shut down' / 'cut power') against a clear resource (the guest VM) and distinguishes the two stopping modes. This separates it from sibling tools like vm_start, vm_reboot, and vm_suspend without needing to open the schema.

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 useful within-tool guidance: soft mode is a graceful shutdown, hard mode cuts power and requires confirm=true. However, it does not explicitly state when to prefer this tool over alternatives like vm_reboot or vm_suspend, or mention any preconditions.

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