vm_resize_disk

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

With no annotations, the description fully discloses that this is a write operation, is destructive and irreversible for growth, and offers a preview mechanism via dry_run. This is comprehensive for a mutation tool.

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 with a header, warning, and an Args list, but the details could be slightly more compact. However, it remains efficient and front-loaded with key information.

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 no output schema and no annotations, the description covers the action, constraints, and all parameters adequately. It omits return value details but is otherwise complete for a disk resize tool.

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?

Despite 0% schema description coverage, the description explains each parameter with examples and context (e.g., 'size: '+<N>G' increment', 'disk: Disk key, e.g. ''scsi0'''), adding significant value beyond the schema's type and title.

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 starts with '[WRITE] Grow a VM disk. GROW-ONLY — shrink requests are refused.' which clearly states the action and a critical constraint, distinguishing it from other disk-related tools like vm_move_disk or vm_reconfigure.

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 guidance on irreversible nature ('No undo token'), preview option ('Pass dry_run=True'), and growth-only constraint. However, it does not explicitly compare with sibling tools like vm_move_disk, leaving implicit differentiation.

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