qemu_vm_command_preview

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

Annotations already indicate read-only, idempotent, and non-destructive behavior. The description adds a critical, non-obvious behavioral trait: the VM remains locked after the preview, requiring a separate unlock call. This goes beyond the annotations and is essential for safe usage, earning a top score.

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 two sentences long and front-loads the core purpose, followed by a crucial side-effect warning. Every word earns its place, with no redundancy or filler.

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?

Given the tool's complexity (12 params, no output schema), the description adequately covers purpose, state-change guarantee, and lock behavior, but leaves a significant gap in parameter semantics and return value format. The lock warning is a strong addition, but the lack of any parameter hints makes the description only minimally complete for a tool of this complexity.

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 has 12 parameters with no descriptions (0% coverage), and the description provides no parameter information whatsoever. For a command-preview tool, the meaning of parameters like 'overrides', 'profile_overrides', or 'extra_args' is not explained, leaving the agent without guidance on how to use them effectively.

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 ('Preview') and resource ('managed QEMU command'), and clarifies the tool's non-mutating nature ('without changing VM state'). This clearly distinguishes it from sibling tools that start, modify, or delete VMs.

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 implies this tool is for inspecting a command before execution, and it explicitly notes that the VM remains locked and instructs the user to call vm_unlock when finished. This provides clear post-usage guidance, though it does not explicitly name alternative tools like qemu_vm_start or qemu_vm_update.

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