start_vm

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

No annotations are provided, so the description carries full responsibility for disclosing behavior. It only states the action without mentioning side effects, idempotency, asynchronous nature, or return values. For a state-changing operation, this is insufficient; an agent cannot infer what happens after calling it.

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 short sentence, which is concise and front-loaded with the core action. It is appropriately sized for a simple tool, though it could be more informative without becoming verbose. The structure is clean and to the point.

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 tool with no annotations and no output schema, the description must explain the operation thoroughly. It only states the basic action, omitting details like whether it returns a task ID, whether it is asynchronous, or whether the VM must be in a stopped state. This is inadequate for an agent to call it correctly with full context.

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% – both 'node' and 'vmid' have clear descriptions. The tool description adds no additional meaning to the parameters, so it does not exceed the baseline of 3. Since the schema fully documents the parameters, a 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 verb 'start' and the resource 'virtual machine', which is specific and directly maps to the tool name. However, it does not explicitly differentiate from siblings like stop_vm or get_vm_status, though the opposite action is implied. It is a clear purpose but lacks any additional context that would distinguish it beyond the name itself.

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?

There is no guidance on when to use this tool versus alternatives. The description only says 'Start a virtual machine' without mentioning prerequisites (e.g., VM must be stopped), typical use cases, or exclusions. Sibling tools are present but not referenced, so an agent gets no help selecting this tool over others.

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