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

Annotations already declare destructiveHint=true, readOnlyHint=false, and idempotentHint=false, so the safety profile is known. The description adds nothing beyond that: it does not say what resource is destroyed or created, whether the source snapshot is modified, or that repeated calls create duplicate copies. For a destructive, non-idempotent operation this is a real gap.

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?

It is a single short sentence with no filler, which is structurally clean. The problem is under-specification rather than wordiness, so it earns only a middling score.

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 destructive, non-idempotent operation with a nested object parameter and no output schema, the definition should at minimum explain what is created/destroyed and how to use the body fields. Nearly all of that is missing, leaving an agent to guess the semantics.

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% across two required parameters, including a nested body with name and auto_stop_minutes. The description never clarifies that id refers to the snapshot, nor what the nested fields mean or that auto_stop_minutes sets an auto-shutdown window (max 10080). The schema's meaning is left entirely unexpanded.

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 restates the name almost verbatim: 'Start a copy from a snapshot' for snapshot_start. The word 'copy' hints that something new is produced, but it never says what is started (a machine? a clone? a restore job?) or how that differs from siblings like snapshot, fork, machine_start, 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?

There is no when-to-use guidance, no prerequisites, and no named alternative. An agent cannot tell from this text whether snapshot_start, fork, or machine_start is the right call for launching an instance from a saved image.

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