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

Annotations already declare readOnly, idempotent, non-destructive and open-world behavior, so the safety profile is covered. The description adds value by disclosing the DoH transport mechanism and that results include TTL, which the annotations do not convey. It does not mention rate limits or caching behavior, which keeps it below a 5.

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 core capability and record types are front-loaded in the first clause, and the use cases follow immediately. The trailing example duplicates the schema's own examples array, which is mild redundancy but not harmful.

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?

With only two parameters, full schema coverage, rich annotations and no output schema, the description supplies what is needed: what is queried, over what protocol, and what comes back (records plus TTL). Nothing critical is missing for correct invocation.

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 description coverage is 100%: the enum of record types, the default of A, and the domain format are all documented in the schema itself. The description only restates the record type list and includes a sample call, adding no new semantic detail beyond the structured fields.

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 verb and resource ('查询域名解析记录') plus the transport ('通过 DNS-over-HTTPS') and the exact record types covered, so an agent knows precisely what it does. It does not need to distinguish itself from siblings, since none of the listed tools overlap with DNS resolution, but it also never states that non-overlap explicitly.

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?

It gives concrete usage contexts: troubleshooting resolution failures, verifying DNS configuration, and inspecting MX/TXT records. There is no explicit when-not guidance or mention of an alternative tool, but the use cases are clear enough to route correctly.

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