Cluster health

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

The annotations already declare readOnlyHint, idempotentHint, and destructiveHint false, so the description does not need to re-establish safety. The description does add useful information about the return content (status, node counts, shard counts), which is helpful because there is no output schema. It does not add deeper behavioral context such as whether includeIndices changes response structure substantially, but that is partially covered by the parameter description.

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 one short, front-loaded sentence: 'Cluster health: status, node counts and shard counts.' Every word earns its place, and 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?

For a simple read-only tool with zero required parameters and a well-documented optional parameter, the description covers the essential return content. The annotations cover the safety profile, and the schema covers the parameter. It is only missing explicit guidance for distinguishing it from cluster_info, which is already penalized under usage guidelines.

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%, and the only parameter, includeIndices, already has a meaningful description: 'Add per-index health detail'. The tool description adds no additional parameter semantics beyond the schema, so the baseline of 3 applies.

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 names the exact resource ('cluster health') and the specific output areas (status, node counts, shard counts), which makes the tool's purpose reasonably clear. It lacks an explicit verb like 'get', but the noun-phrase style with tool name 'elasticsearch_health' is sufficient. It is distinguishable from index-focused siblings like list_indices and get_mappings, though cluster_info could overlap without more detail.

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 no guidance on when to use this tool versus alternatives. With sibling cluster_info likely covering similar cluster-level information, the absence of a routing note is a real gap. Any usage guidance is only implied by the name and the word 'health'.

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