vm_clone

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

Annotations only indicate readOnly=false and destructive=false. The description adds valuable behavioral context: the clone is a full independent copy, it is slow and consumes full disk space, and cloning a running VM may capture a crash-consistent disk. It also discloses the return value format.

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?

Three short, front-loaded paragraphs with no filler. The '[WRITE]' marker, core operation, default behavior, return type, cost/performance caveat, alternatives, and consistency warning all earn their 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 tool with six parameters and an output schema, the description fully covers the practical calling context: placement defaults, return value, cost profile, alternatives, and runtime consistency caveat. Nothing needed for correct selection or invocation is missing.

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 documents all six parameters with 100% coverage, so the baseline is 3. The description synthesizes the to_host/to_datastore defaults into one phrase ('source's host+datastore'), but this largely restates what the schema already says rather than adding new parameter meaning.

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?

States a specific verb and resource ('Clone a VM') and makes the output explicit ('Returns a status string naming the clone'). It also distinguishes itself from siblings by naming deploy_linked_clone and batch_clone_vms as different tools for different use cases.

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?

Explicitly tells the agent when to prefer alternatives: 'prefer deploy_linked_clone for near-instant test copies and batch_clone_vms for many at once.' It also provides a practical caveat about cloning a running VM, which helps the agent decide whether this tool is appropriate.

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