create_vm

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

With no annotations, the description carries the full burden and does well: it starts with 'DESTRUCTIVE:', explains the confirm mechanism ('Must be true to execute. Returns a preview otherwise'), and warns about state changes. It does not cover permissions or failure modes, but it adds significant context beyond the schema.

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 well-organized and front-loaded with the purpose. The parameter list in a code block is compact and every sentence adds value—no fluff or redundancy. It remains readable despite covering 8 parameters.

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?

The description is complete for invoking the tool: it covers all parameters, provides common values, and explains the confirmation flow. It does not mention edge cases like resource limits or cleanup, but the lack of annotation makes it comprehensive. An output schema exists, so return values need not be detailed.

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 0%, so the description must compensate. It explains every parameter, provides allowed values for os_type ('ubuntujammy', 'debian12', etc.), BIOS options ('ovmf', 'seabios'), and auto_start policies ('on', 'off', 'last'). It also lists defaults for each parameter, making it extremely helpful.

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 immediately states 'Create a new virtual machine' with a detailed explanation of resource configuration. It clearly differentiates from sibling tools like clone_vm (which duplicates an existing VM) and import_vm_file (which imports an existing file).

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 provides clear guidance on parameter values (os_type, bios, auto_start) and the confirm requirement, but does not explicitly contrast with alternatives like clone_vm or import_vm_file. It gives context on how to use the tool effectively.

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