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

With idempotentHint=true and destructiveHint=false already provided by annotations, the description adds valuable context with 'Same disk, same address', disclosing that state persists across start/stop cycles. No contradiction with annotations, and the added behavioral detail is meaningful beyond what the annotations convey.

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 exceptionally concise—two short phrases—yet conveys the action, object, and a key behavioral promise. Every word earns its place, and the structure front-loads the action and resource.

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 simple one-parameter tool with an idempotent safety hint and no output schema, the description is complete. It states what the tool does and adds persistence context, while the sibling list and annotations provide additional context. No significant 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 schema already covers 100% of the single parameter 'id' with a description 'Machine id'. The tool description adds no additional parameter semantics, so it meets the baseline for high schema coverage but does not exceed it.

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 'Start a stopped persistent Linux machine' clearly names the specific action (start) and resource (persistent Linux machine), and distinguishes it from siblings like stop, create, and delete. The phrase 'Same disk, same address' further clarifies what starting means in this context, making the purpose unambiguous.

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 the tool is for stopped machines, which gives clear context for when to use it. It does not explicitly mention alternatives or exclusion scenarios (e.g., when not to use), but for a simple start operation the context is sufficient to guide selection among siblings.

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