services_networks_change_ipv4

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

Annotations already declare destructiveHint=true, idempotentHint=false and openWorldHint=true, so the risk profile is covered. The description adds genuinely new context that the operation is billable ('one-time payment') and exposes the underlying endpoint. It does not say what happens to the replaced address, whether the change is reversible, or what the payment failure behavior is.

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 lines, zero filler, with the action and the payment condition front-loaded before the endpoint. It is terse to the point of omitting useful detail, but nothing present is wasted.

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?

This is a destructive, billable mutation with a nested body object and no output schema, which sets a high bar. The description covers the action, the cost, and the endpoint, but omits what the replacement does to the existing address, payment failure consequences, and any precondition on the service state.

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 0% for three required parameters, so the description must carry weight. The URL template does clarify that serviceId and externalId are path identifiers and that externalId refers to the IPv4 entry being changed, which is real added meaning. However, the nested body.method parameter (payment method slug) is never addressed in the description, and neither is whether externalId is the old or new address.

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 gives a specific verb and resource: 'Change (replace) IPv4 address', plus the exact REST endpoint, so an agent knows precisely what operation this performs. It does not name or contrast with the closest sibling (services_networks_buy_ipv4), so differentiation is left implicit.

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 only usage signal is 'for a one-time payment', which hints at a cost implication but never states when to choose this over buying a new IPv4 or making an address primary. No prerequisites, no exclusions, and no mention of checking price first via services_networks_ipv4_get_price.

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