vm_backup

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

Discloses it is a write operation, returns a UPID, and explains mode effects on downtime. Without annotations, it covers key behavioral traits but lacks details on permissions or performance impact.

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 very concise: a one-line summary followed by bullet-point argument explanations. Every sentence adds value, and it is front-loaded with the WRITE tag and core purpose.

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?

Covers all 5 parameters and provides useful defaults and references. Lacks error conditions or return format beyond 'UPID', but overall complete for a backup creation tool given no output schema.

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?

With 0% schema coverage, the description compensates fully by explaining each parameter: vmid (numeric ID), storage (backup-capable), mode (snapshot/suspend/stop with default), target (from config), node (optional, auto-locate). Adds significant meaning beyond the schema.

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 explicitly states it creates a vzdump backup of a VM/CT to storage, with a [WRITE] prefix and returns a task UPID. This clearly distinguishes it from siblings like backup_list or backup_restore.

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?

Provides context on arguments (e.g., mode options, node auto-location) and references related tools (storage_list, storage_content). Does not explicitly state when not to use or compare directly to alternatives, but the context is sufficient for typical use.

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