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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds the useful fact that both custom and Railway-generated domains are returned along with verification status, but says nothing about result size, ordering, or how verification status is represented.

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?

A single front-loaded sentence with no filler; the verb and resource lead and the returned attribute follows. Nothing in the sentence is redundant given the structured fields.

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?

With no output schema and zero parameter documentation, the description is the only narrative an agent gets. It covers what is returned but omits the required service/environment/project scoping and any hint of result shape, which is the main gap for a 10-parameter read tool.

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% across 10 parameters, so the description carries the full burden and fails to carry it: the three required scoping identifiers (projectId, environmentId, serviceId) are never mentioned, nor are the Beon framework parameters. An agent cannot tell from the description that the listing is service-scoped rather than account-wide.

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 names a specific verb (List) and resource (custom and Railway generated service domains) plus the attribute returned (verification status), so the agent knows exactly what comes back. It does not, however, differentiate itself from the adjacent railway_get_domain_status or the create/delete domain siblings.

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?

There is no statement of when to use this tool versus railway_get_domain_status (single-domain status) or the create/delete domain tools. The only implicit guidance is the word 'List', leaving the agent to infer that this is the discovery step before a status or delete call.

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