create_domain_record

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

Although idempotentHint already signals repeatability, the description adds valuable behavioral context: DNS propagation may take minutes, issue_cert re-checks resolution itself, and retrying issue_cert is safe if the domain is not yet resolving. This goes beyond the annotations and helps the agent anticipate timing and failure behavior.

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 tight and front-loads the core purpose before providing workflow guidance. The sentence about repeatability overlaps with the idempotentHint annotation, which prevents a perfect score, but the remaining sentences all earn their place.

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 rich schema, existing annotations, and presence of an output schema, the description fills the remaining practical gaps: where this tool fits in the provisioning flow, DNS propagation delays, retry safety, and which sibling tool to use instead. Nothing necessary for correct invocation is missing.

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 input schema documents all three parameters with descriptions and examples, so parameter semantics are fully covered by structured data. The description restates domain→target but adds no new constraints, syntax, or edge-case guidance beyond what the schema already provides.

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?

Clearly identifies the operation as an upsert of a Route 53 CNAME record pointing `domain` at `target`, which is specific and unambiguous. It also distinguishes itself from create_txt_record and from create-only semantics, so an agent can immediately tell what this tool does and does not do.

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?

Provides explicit sequencing ('Run this before create_site / issue_cert'), timing guidance ('allow a few minutes for DNS propagation'), and a clear alternative for TXT records ('use create_txt_record instead'). This gives the agent concrete conditions for when to invoke this tool versus a sibling.

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