Create DNS record

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

Annotations already declare readOnlyHint=false, destructiveHint=false, openWorldHint=true, so the agent knows this is a mutating but non-destructive external-facing write. The description adds that value shape depends on type and references docs, plus a duplicate-avoidance workflow. However, it doesn't disclose auth requirements, success/failure semantics, or what the response contains for a complex mutation tool.

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?

Three short, front-loaded clauses: a write marker, endpoint, and a usage hint. No wasted words, though the docs reference is somewhat terse. Efficient for the space given.

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 11 params, nested objects, no output schema, and a 9% schema description coverage, the description is far too sparse. It fails to explain the excluded/mutually-exclusive nature of parameters, type-specific value requirements, or return behavior, leaving the agent underinformed to call it correctly.

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 9% for 11 parameters, so the description must compensate. It only addresses 'value shape depends on type' and omits any meaning for the many undocumented parameters (ttl, cloud, usage, selector, matching_type, ip_filter_mode, upstream_https) and even the base ones. Most parameters remain opaque to the agent.

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+resource ('Create a DNS record'), names the exact API endpoint, and is clearly distinguishable from siblings like update_dns_record, delete_dns_record, and set_dns_record_cloud. The '[WRITE]' tag and endpoint make the operation unambiguous.

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?

Gives a clear directive ('Inspect current records before creating duplicates') which implies using list_dns_records first, and points to docs for value shape. It provides usage context but doesn't explicitly name the sibling tools or state when NOT to use this (e.g., use update_dns_record for existing records).

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