IndexMappingTool

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

No annotations are provided, so the description must carry the full burden. The word 'Retrieves' implies a read-only operation, but the description doesn't disclose whether permissions are needed, how errors are handled (e.g., missing index), or whether any side effects occur. There is no mention of the return format or additional behaviors.

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, 12-word sentence that front-loads the purpose. Every word is useful; there is no redundancy or 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?

This is a very simple tool with one parameter, no output schema, and read-only implication. The description explains what it does and what input it takes, which covers the essential context. It doesn't mention return format or error scenarios, but the phrase 'mapping and setting information' gives a reasonable idea of the output. It could be slightly richer, but for the tool's simplicity it is largely complete.

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 input schema has a single 'index' parameter with no description, and coverage is 0%. However, the description's phrase 'for an index in OpenSearch' clarifies that the parameter refers to the name of the index. This adds meaning beyond the bare schema, though it doesn't provide format constraints, examples, or edge-case semantics.

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 verb ('Retrieves'), the resource ('index mapping and setting information'), and the target ('an index in OpenSearch'). This distinguishes it from sibling tools like ListIndexTool (list indices), SearchIndexTool (search data), and GetShardsTool (shard info).

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 provides no explicit guidance on when to use this tool versus alternatives. It doesn't mention prerequisites, exclusions, or when ListIndexTool or GetShardsTool would be more appropriate. The intended use is only implied by the tool name and the phrase 'for an index'.

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