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

Beyond the annotations (readOnlyHint=false, destructiveHint=false), the description discloses three non-obvious traits: the change is staged rather than immediately live, a custom hostname returns DNS records the member must act on, and "This call asks no human" – useful given the presence of approval-related siblings. It stops short of covering conflict/error behavior or reversibility via domain_remove.

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 short sentences, front-loaded with the core action and mode split, followed by staging behavior, the DNS return, and the no-approval note. No sentence is filler and the most important constraint leads.

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?

There is no output schema, and the description compensates by saying a custom hostname returns DNS records to create. For a 7-parameter mutation with annotations present, the main remaining gap is what happens on failure or when a domain already exists on the service.

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?

With 86% schema description coverage, the schema already documents port, prefix, hostname, project, environment and expect_revision well, including the prefix/hostname mutual exclusion. The description only restates the hostname-vs-generated distinction and adds no syntax, format, or default details beyond it, so the 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?

The description gives a specific verb+resource ("Give a Service a public domain") and immediately distinguishes the two modes it supports: a member-owned hostname or a Ployz Cloud generated one under the cluster domain. Against siblings like domain_update, domain_remove and domain_check, the additive nature is 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?

It supplies operational context ("Staged until the next Deploy") and notes the DNS-record consequence for custom hostnames, which implies when the call is appropriate. However, it never names an alternative or states a when-not – nothing tells the agent to prefer domain_update for an existing domain or domain_check to verify one. Usage is implied, not guided.

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