VPS_setHostnameV1

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

The description discloses that changing hostname does not update PTR records automatically and that domain records must be pointed. With no annotations, this provides some behavioral insight but does not mention potential side effects, permissions required, or whether a restart is needed.

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 relatively concise, gets to the point quickly, and includes important caveats. However, the caveats about PTR and domain records could be more succinct.

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 mutation tool with 2 parameters and 100% schema coverage, the description adequately explains the core action and key side effects. It does not specify return values or confirm success, but no output schema provides for that. Missing details like potential delays or reboot requirements.

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 100%, so baseline is 3. The description does not explain parameter constraints beyond what the schema provides, such as acceptable hostname formats or length limits.

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 clearly states the tool's purpose: 'Set hostname for a specified virtual machine.' It differentiates from related siblings like VPS_resetHostnameV1 by specifying 'set' vs 'reset' and provides additional context about PTR and domain records.

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 advises when to use the tool ('Use this endpoint to configure custom hostnames for VPS instances') and includes caveats about PTR records and domain A/AAAA records. However, it does not explicitly contrast with alternatives like VPS_resetHostnameV1.

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