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

With no annotations, the description carries the full burden and does so: it flags destruction upfront, states the change is immediate ('stops resolving through that record immediately'), declares irreversibility ('there is no undo'), and specifies what is preserved (the name and every other record). Only auth/permission requirements are absent, which is a minor omission for an unannotated 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?

Four sentences, zero filler, and the destructive warning plus scope are front-loaded before the parameter clarification and the irreversibility note. Every sentence carries distinct information.

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 an unannotated mutation tool with no output schema, the description supplies the safety profile (destructive, immediate, irreversible), the routing decision against delete_domain, and the id-vs-name disambiguation. Nothing essential for a correct call is missing.

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 coverage is 100%, so all three parameters are already documented in the schema, including the identical 'id not name/type/content' warning for record_id. The description's only genuine addition is provenance — that the id comes from get_domain and is returned by claim_domain and add_dns_record — which is marginal, so baseline 3 applies.

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 ('permanently remove ONE DNS record from a subdomain'), quantifies scope (one record, not the whole name), and explicitly names the sibling it is not (delete_domain). An agent can distinguish it from every other sibling without opening a schema.

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 concrete when-to-use triggers ('undo a single record — a wrong IP, a spent ACME challenge') and an explicit exclusion with the alternative to prefer instead ('instead of delete_domain, which takes the whole name'). Routing is unambiguous.

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