Change Primary IP Reverse DNS

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

Annotations provide idempotentHint=true and destructiveHint=false, indicating the operation is non-destructive and safe to retry. The description adds the behavior of resetting via null, which is already in the schema description for dns_ptr. However, it does not disclose whether other settings are affected, what happens if the IP is not assigned, or any authorization requirements.

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?

Two sentences, no unnecessary words. Front-loaded with the main purpose followed by a key behavioral note. Highly efficient.

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?

Given the lack of output schema, the description does not mention what is returned (e.g., the updated primary IP object). For a simple mutation with 3 params, it covers the basic action but lacks information about error scenarios or required resource state (e.g., the primary IP must exist and not be in use or something). Adequate but not comprehensive.

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% with clear descriptions for all three required parameters. The description's extra statement about null reset is redundant with the schema description. No additional semantics beyond the schema are provided, so baseline 3 is appropriate.

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?

Description clearly states the tool changes reverse DNS for a primary IP, with specific verb 'change' and resource 'primary IP'. It also mentions the special case of setting dns_ptr to null to reset. The name and title match the description, and it is distinct from sibling tools like hetzner_change_floating_ip_rdns by explicitly stating 'primary IP'.

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?

No guidance on when to use this tool versus alternatives like hetzner_change_floating_ip_rdns or hetzner_change_dns_ptr. No prerequisites or conditions for use are mentioned. The description only states the action without any context on appropriate scenarios.

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