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

With no annotations present, the description carries the full burden and does well: it declares the operation is mutating and lists server-side enforcement (CNAME coexistence conflicts, per-zone quota, per-type validation). It stops short of stating required permissions, whether the operation is reversible, or what happens on a rejected conflict.

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, front-loaded with the action and scope, with no filler. The long parenthetical type list is somewhat redundant with the enum but is compact enough to justify itself.

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 mutation tool with no annotations, no output schema, and low parameter coverage, the description covers behavior but omits auth/permission requirements and gives no indication of the response. The core is adequate but leaves real gaps an agent must guess at.

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 only 20% (only 'name' is described in the schema), so the description should compensate but does not: it restates the record-type set already captured by the enum and says nothing about ttl bounds, content format, or zoneId. TTL, content, and zoneId remain undocumented in both places.

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?

States a specific verb and resource ('Create a DNS record') plus the scope ('in your zone') and enumerates every supported record type, so the agent knows exactly what is produced. It does not explicitly name or distinguish itself from siblings like dns_record_update, dns_record_delete, or dns_records_import, leaving that differentiation to inference from the verb.

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?

There is no when-to-use guidance, no prerequisite statement, and no pointer to the alternatives (update, delete, import) that an agent would need to pick the right tool. The description explains enforcement rules but never tells the agent when this tool is the correct choice.

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