Get domain

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds useful content disclosure (the response includes a DMARC policy snapshot and the RUA tag to publish), but with no output schema it does not describe remaining fields, auth needs, or error 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?

One compact sentence with no filler, front-loaded on the resource and key. It is a noun-phrase fragment rather than a full sentence, and 'the RUA tag to publish' is slightly compressed, but nothing is wasted.

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 simple single-record getter with annotations covering safety and a fully documented parameter, the definition is adequate. With no output schema, however, the description only partially describes the return payload and omits behaviors such as not-found handling, so a gap remains.

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?

There is a single required id parameter with 100% schema description coverage, including the hint that it comes from list_domains. The description adds nothing about the id beyond the schema, so the baseline of 3 applies.

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 names a specific resource (one domain) and its retrieval key (by id), and lists the distinctive payload it returns (DMARC policy snapshot, RUA tag), so an agent can separate it from list_domains. It lacks an explicit verb and does not name a sibling directly, so it falls just short of a 5.

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?

Usage is only implied: the 'by id' phrasing and the schema note that the id comes from list_domains suggest a list-then-detail flow. There is no explicit when-to-use statement, no exclusions, and no named alternative.

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