object_storage_find_by_region

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

With no annotations, the description carries the burden of behavioral disclosure. It states that the operation returns a list of instances, implying a read-only lookup, but does not mention pagination, ordering, or behavior when a region code is invalid.

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 compact and front-loaded, with a clear one-sentence purpose followed by Args and Returns sections. Every line adds useful information with no filler.

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?

For a simple one-parameter lookup with an output schema present, the description covers purpose, parameter meaning, and return type. Minor gaps remain around valid region codes and pagination, but nothing that critically blocks a call.

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 schema provides only a bare string for 'region' with zero coverage, so the description must compensate. It adds the key clarification that region is a region code and gives concrete examples ('ewr', 'lax', 'fra'), though it does not enumerate all valid codes or point to a source for them.

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?

Begins with a specific verb+resource: 'Find all Object Storage instances in a specific region.' The qualifier 'by region' distinguishes it from sibling object_storage_get and object_storage_list_clusters, so an agent can infer what it does without opening the schema.

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 makes the context clear: use it to find Object Storage instances in a specific region. However, it does not explicitly say when to prefer this over alternatives such as object_storage_get or object_storage_list_clusters, nor give any exclusion criteria.

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