qemu_vm_update

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

Annotations indicate readOnlyHint=false and destructiveHint=true, but the description adds useful behavioral context beyond that: the VM must be stopped and remains locked, requiring a follow-up unlock. This is valuable operational nuance not present in the annotations. No contradiction exists.

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, front-loaded with the core action, and every clause adds value: the scope of updates, the stopped requirement, and the lock/unlock instruction. No wasted words or redundancy.

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?

Despite complexity (12 params, nested objects, no output schema, destructive hint), the description covers the key precondition (stopped) and the post-requirement (unlock). However, it doesn't mention return value, failure modes, whether the update is a full replacement or merge, or what 'managed' implies. This leaves gaps for an agent needing to fully anticipate outcomes.

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 carries the burden for explaining parameters. It only hints at 'accelerator policy' and 'any profile component', which loosely map to acceleration and profile-related parameters, but leaves the remaining 10+ parameters wholly unexplained. This is insufficient for a 12-parameter tool.

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 tool updates a 'stopped managed QEMU VM definition' with a specific verb and resource, and distinguishes it from siblings by emphasizing the stopped state and definition-level scope. It also mentions coverable areas like accelerator policy and profile components, adding specificity.

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 explicitly notes the VM must be stopped and that it remains locked by this session, requiring vm_unlock afterward. It provides clear context for when to invoke the tool, though it doesn't explicitly name alternative tools for comparison, the precondition and lock instruction are valuable guidance.

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