Update DNS Zone RRSet Record Comments

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

Annotations already indicate this is a non-read-only, idempotent, non-destructive mutation. The description adds behavior beyond that: records are matched by existing value, only the comment field is affected, and an empty string clears the comment. This gives the agent useful expectations about what the operation changes.

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 short, information-dense sentences. The core behavior is stated first, and the important always-sent/clearing nuance is included without redundancy or filler.

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 focused comment-update operation with fully documented schema parameters, the description is complete enough for an agent to understand the operation, matching semantics, and clearing behavior. It does not describe response/return values, but no output schema exists and the operation is narrow enough that this is a minor omission.

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%, so the schema already documents all parameters and their semantics. The description reinforces the value-matching behavior and the empty-string-to-clear rule, but does not add substantial meaning 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?

The description uses a specific verb ('Update') and resource ('comment on existing records in an RRSet'), and critically adds the matching criterion 'matched by value', which distinguishes it from related siblings like set_zone_rrset_records, add_zone_rrset_records, and remove_zone_rrset_records. An agent can tell exactly what this tool does and what it 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?

The description gives clear usage context: it targets existing records matched by value, and it explains that the comment field is always sent, with an empty string to clear. It does not explicitly name when-not-to-use alternatives, but the 'existing records' and 'comment only' framing makes the intended scope clear enough.

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