get_otlp_metric_names

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds value by noting the feature flag requirement and the friendly notice when unavailable, which is behavioral context beyond the annotations. It doesn't describe pagination or return format, but the annotations carry the safety burden.

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 sentence that front-loads the core purpose ('List metric names'), then adds the key prerequisite (feature flag) and behavior (friendly notice). Every word earns its place, and the [PREVIEW] tag is appropriately placed at the start.

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 read-only list tool with 100% schema coverage and no output schema, the description covers the essential context: what it does, the feature flag requirement, and the unavailable behavior. It doesn't mention pagination or result ordering, but these are minor gaps given the tool's simplicity and the annotations covering safety.

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 all four parameters (end, limit, start, contains) are already documented in the schema. The description doesn't add parameter-level detail beyond what the schema provides, which is acceptable given the high coverage. The baseline of 3 applies here.

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 tool lists metric names ingested via native OpenTelemetry (OTLP), with a specific verb ('List') and resource ('metric names'). It distinguishes itself from sibling tools like get_otlp_metric_labels, get_otlp_label_values, and query_otlp_metrics by focusing on metric names specifically.

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 mentions the OTLP Metrics feature flag requirement, which is a clear prerequisite for using this tool. It doesn't explicitly name alternatives or when-not-to-use conditions, but the '[PREVIEW]' tag and feature flag note provide useful context. The sibling list includes related OTLP tools, but the description doesn't explicitly route between them.

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