List indices

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

No annotations are provided, but the description discloses important runtime behavior: it tries _cat/indices when the credential has the monitor privilege and falls back to _resolve/index otherwise. This privilege-dependent fallback is exactly the kind of behavioral detail that helps an agent understand what will happen on invocation.

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?

Three dense sentences, no filler. The main purpose is stated first, followed by route behavior, then usage guidance. Every sentence contributes distinct information.

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?

The description covers the tool's purpose, auth-dependent routing, and fallback strategy. It does not describe the differing output formats of _cat/indices versus _resolve/index, but since there is no output schema, an agent may still lack full clarity about response shape.

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 already documents the pattern parameter with a default and examples (100% coverage). The description only restates that indices are matched by pattern, adding little semantic value beyond the schema.

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 starts with a specific verb and object: 'List Elasticsearch indices matching a pattern.' It also positions itself as the starting point for index discovery, which distinguishes it from sibling tools like es_get_mappings or kbn_list_data_views.

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 gives explicit guidance: use this tool when you do not know which index holds the data, and name the fallback tool (kbn_list_data_views) if both API routes are forbidden. This clearly tells an agent when to select this tool over alternatives.

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