qemu_vm_select

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

Annotations are sparse (readOnly=false, destructive=false), but the description adds crucial behavioral context: the VM remains locked by this session, implying a session-scoped side effect and a required finalization step (vm_unlock). It also clarifies that this tool does not affect in-guest MCP control. This goes beyond annotation-provided information, though it doesn't cover repeat behavior or lock conflicts.

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 exactly two sentences and front-loads the primary purpose in the first sentence. The second sentence adds essential scope and lock guidance without any filler or repetition. Every phrase earns its place.

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 simple selection tool with one parameter and no output schema, the description covers the key aspects: what it does, session scope, locking, and the need to unlock. It does not mention potential errors, return values (none), or what happens if another VM is already selected, but these are not critical for such a basic operation. The guidance to call vm_unlock adds completeness.

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%, and the description does not mention the vm_id parameter at all. While the parameter is a simple string with a pattern, the tool name implies it selects a VM, but the description should ideally specify that vm_id identifies the target VM (e.g., via qemu_vm_list). The description adds no additional meaning to the parameter beyond what the schema already exposes.

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 records the selected QEMU VM for the session's QEMU panel, distinguishing it from siblings like qemu_vm_list (listing) and qemu_vm_unselect (deselecting). The verb 'Record' and the specific resource ('managed QEMU VM selected in this MCP/Admin session's QEMU panel') make the purpose unambiguous.

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 context on when to use it: it's for session-level selection, not for in-guest control (explicitly stated as 'In-guest MCP control remains the agent's outbound TCP connection'). It also instructs to call vm_unlock when finished. However, it does not name alternative tools (e.g., qemu_vm_unselect) or explicitly state when not to use, leaving some room for inference.

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