set_domain_dns

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

No annotations are provided, so the description carries full burden. It states 'Plain write — not gated', declares the full replacement nature of the 'records' parameter (up to 100), and explains the error condition. It omits mention of return value, but the operation is straightforward.

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 concise, front-loading the main action. It uses three dense sentences, each providing essential information: operation, prerequisite, error condition, scope requirement, and parameter details. No redundant words.

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 tool's simplicity (2 parameters, no output schema), the description covers the function, prerequisites, error case, and parameter details. It could explicitly state the destructive nature (full replacement) but that is implied. Overall, it is thorough for the tool's complexity.

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%, and the description adds significant value: explains that 'id' comes from list_domains, describes 'records' as a full replacement set (up to 100), details required fields (hostname, type, address), and specifies 'priority' usage for MX/SRV. This goes beyond the schema descriptions.

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 'Replace an owned domain's DNS host records', specifying the action and resource. It distinguishes itself from siblings like 'get_domain_dns' (read) and 'set_domain_nameservers' (different record type). The mention of registrar dependency adds specificity.

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 notes the required scope 'domains:write', specifies that 'id comes from list_domains', and warns about the 'not-implemented error' for registrars without a DNS API. It does not explicitly contrast with alternatives like partial updates, but the context is clear.

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