GetShardsTool

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

With no annotations, the description must carry the burden of behavioral disclosure, but it only says 'Gets information,' which implies read-only without detailing side effects, return shape, or failure behavior. It does not state what shard information is included or how authentication-related behaviors affect the call.

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 a single, front-loaded sentence with no redundant phrasing. It is appropriately terse, though it may err slightly on the side of under-specification rather than over-explaining.

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?

This tool has 11 parameters and no output schema, and the description provides minimal context about what 'information about shards' means or what the caller should expect in return. For an agent to use it correctly, more detail on the shard data returned or typical use cases would be needed.

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%, so the input schema fully documents each parameter, including index, endpoint, and authentication options. The description itself adds no extra parameter semantics beyond the context that the tool targets shards, maintaining the baseline score.

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 uses a clear verb ('Gets') with a specific resource ('information about shards in OpenSearch'), which differentiates it from cluster-level or document-level sibling tools. It is slightly generic about what aspect of shards is returned, but it clearly identifies the tool's scope.

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 explicit guidance about when to prefer this tool over siblings such as GenericOpenSearchApiTool or ClusterHealthTool. The use case is implied by the description: retrieve shard-level information for a named OpenSearch index. This is adequate but not instructive.

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