get_otlp_label_values

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

Annotations already cover the read-only and idempotent behavior, so the description only needs to add extra context; it does add [PREVIEW] status and 'observed' to signal the result set is data-dependent and possibly incomplete. It does not describe return format, default time-window behavior, or pagination, and there is no contradiction with the annotations.

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 an illustrative example and no filler. It does not repeat schema details or annotation flags.

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 low-complexity read-only list operation, the definition and schema together give enough to invoke it correctly: resource, example, and all parameter descriptions. It leaves minor ambiguity about output shape and behavior when start/end are omitted, which prevents a 5.

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 already explains key, start, end, limit, and metric, including the label-name discovery hint on key. The one-line tool description does not add parameter-level meaning beyond the example service_name, so the baseline 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 a specific verb and resource: it lists values observed for one native OTLP metric label, with service_name as an example. This clearly distinguishes it from the sibling get_otlp_metric_labels, which discovers label names rather than their values.

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 intended use is clear: get value options for a single OTLP label. The key parameter schema also routes the agent to get_otlp_metric_labels for discovering label names, which is useful sibling guidance, though the description itself does not make when-not or alternatives explicit.

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