object_storage_list_clusters

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

No annotations are provided, so the description carries the burden. It discloses that the tool returns a list of clusters with specific fields (id, region, hostname, deploy), which is useful. However, it doesn't mention whether this is a read-only operation, whether it requires authentication, or whether there are any rate limits or pagination. The return format is partially disclosed via the field list, but the description doesn't state the overall response structure beyond 'List of Object Storage clusters with details.'

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?

The description is concise and front-loaded with the main purpose in the first sentence. The return field list is useful and not overly verbose. It could be slightly more structured (e.g., using a more compact format), but it's efficient and every sentence earns its place.

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?

Given that this is a simple zero-parameter list operation with an output schema present, the description is nearly complete. It names the resource, the scope ('all available'), and the key return fields. It doesn't mention authentication or pagination, but for a simple list tool with an output schema, this is a minor gap. The presence of an output schema reduces the need to explain return values in detail.

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?

The tool has zero parameters, so there is no parameter semantics burden on the description. The schema is empty and coverage is 100% (trivially). The description correctly focuses on the return value instead. A baseline of 4 is appropriate for a no-parameter tool.

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 clearly states the tool's purpose: 'List all available Object Storage clusters.' It uses a specific verb ('List') and resource ('Object Storage clusters'), and the name itself is unambiguous. It also distinguishes itself from sibling tools like object_storage_get (which retrieves a single cluster) and object_storage_list_cluster_tiers (which lists tiers, not clusters).

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 description implies usage context: it's a read-only listing operation for all available clusters, with no parameters required. It doesn't explicitly state when to use this vs alternatives, but the 'all available' phrasing and the sibling tool names (object_storage_get, object_storage_find_by_region) make the use case reasonably clear. It lacks an explicit exclusion like 'use object_storage_get for a single cluster's details.'

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