Update RRSet labels

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

The description reveals the key behavior that the provided labels replace all existing labels, which is critical for an agent to understand the destructive/replacement nature. While annotations provide idempotentHint, the description adds context beyond that. It does not discuss potential side effects or permissions, but those are covered by standard domain knowledge, so a 4 is appropriate.

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 two sentences long, front-loaded with the primary purpose, followed by a clarifying note and a pointer to alternatives. There is no redundant information 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?

The description is highly complete for the tool's job: it explains the replacement behavior and what the tool does NOT do (records/TTL). It lacks explicit mention of the return value, but given the idempotent hint and simplicity, this gap is minor. It effectively uses sibling tool mentions to complete the context.

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 has 100% coverage for all four parameters, providing thorough descriptions. The description adds no additional parameter-level semantics beyond stating that the set replaces existing labels, which is an operation-level detail. Therefore, a baseline score of 3 is justified.

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 explicitly states 'Update the labels of an RRSet' with a specific verb and resource. It further clarifies that 'the given set replaces all existing labels,' distinguishing it from partial updates. The pointer to 'set_records/add_records/remove_records and change_rrset_ttl' for records and TTL clearly differentiates it from sibling tools.

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 provides explicit guidance on when to use this tool: only for updating labels. It explicitly excludes records and TTL changes, directing the agent to the appropriate sibling tools. This makes the usage context unambiguous.

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