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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds the underlying API route (GET /1.3/object-storage-2) and the shape of returned entities, which is useful context beyond the annotations, but it says nothing about pagination behavior, result volume, or auth scoping.

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 compact fragments with the resource and its returned fields front-loaded, then the API reference. Nothing is wasted, though the sentence is terse enough that it reads more like a field dump than a directive.

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, so the field enumeration in the description does real work in telling the agent what comes back. Combined with the readOnlyHint annotation and the fully documented parameters, the definition is nearly self-sufficient; only routing/pagination guidance is absent.

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 100%, and each of sort/limit/offset already documents defaults, ranges, and the descending-prefix convention. The description adds no parameter meaning at all, so the baseline 3 for a fully documented schema is appropriate.

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 the resource precisely ('Managed Object Storage (S3-compatible) services') and enumerates the fields returned (uuid, name, region, status, endpoints, domains, labels), which tells an agent this is a read/list operation over object-storage services. It implicitly distinguishes itself from the block-storage sibling upcloud_list_storages via 'S3-compatible' and the endpoint, but never names or contrasts that sibling explicitly.

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 when-to-use guidance, no mention of when to prefer upcloud_list_storages or upcloud_get_storage, and no stated prerequisites or pagination caveats. The agent must infer usage purely from the resource name.

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