kd_setup_host

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

With no annotations, the description carries the behavioral burden. It does disclose a real side effect: modifying the vmx by adding a COM port, plus the VM-off prerequisite. However, the net path is vague—'reports the one-time firewall step' could mean it merely prints instructions or that it actually performs a firewall change—and there is no mention of idempotency, permissions, or return behavior.

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 one dense sentence that front-loads the main purpose and then compresses the serial and net variants. It is reasonably concise, though the compact split between serial and net creates mild ambiguity about how the mode is selected.

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 one-parameter tool, the description includes the essential purpose, a concrete file modification, the VM-off prerequisite, and an output-like behavior for net. It is incomplete because it does not explain how the serial versus net path is chosen or whether the net step actually modifies the firewall or only reports the command, and there is no output schema or annotation to fill those gaps.

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 already fully documents the single 'vm' parameter with 'VM name as registered in vms.yaml', so the description contributes no additional parameter-level meaning. With 100% schema coverage, the baseline score of 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 that this tool prepares the host side of the kd transportched and gives concrete detail for both serial ('adds the named-pipe COM port to the vmx') and net ('reports the one-time firewall step'). It is distinguishable from sibling kd_setup_guest because the host side is explicit, though the mode-dependent behavior could be spelled out more clearly.

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 when to use it: host-side kd transport setup. It also discloses the important prerequisite that the VM must be off for the serial path. However, it does not explicitly name kd_setup_guest as the alternative or state when this tool should not be used, so the guidance is more implied than explicit.

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