add_ip_to_vps

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

Beyond the annotations (which only indicate it is not read-only, not open-world, not idempotent, and not destructive), the description discloses the most important behavioral trait: 'Spends real money — requires confirm=true.' This financial side effect is critical for an agent deciding whether to invoke the tool and provides context the annotations do not.

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 sentences, each earning its place: the action, the financial/confirmation warning, and the sibling routing. Information is front-loaded and there is no redundant text or restatement of the tool name.

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 financial mutation with two parameters and no output schema, the description covers the core essentials: what it does, the prerequisite (confirm=true), and the alternative path. An agent can correctly invoke this tool and avoid misuse without additional information.

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 coverage is 0%, so the description carries the burden of explaining parameters. It clarifies that confirm must be true for the purchase to execute, which adds meaning to the boolean parameter. The vps_id is implied by 'this VPS' in the description, but no formatting or source information is provided; still, enough is conveyed for correct invocation.

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 begins with a specific verb phrase: 'Purchase and attach a brand-new IP address directly to this VPS.' This states the exact action and resource, and the adjective 'brand-new' distinguishes it from attaching an existing IP via attach_ip. The purpose is unmistakable and distinct from sibling tools.

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 explicitly names the alternative for a different use case: 'To attach an IP you already own instead, see attach_ip.' It also tells the agent that confirm=true is required, establishing the precondition for using this tool. This is clear routing guidance.

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