system_metrics

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

With no annotations, the description carries the full burden and does so well: it discloses the auth scheme (Basic-auth, not panel Bearer token), the required credentials, and the failure mode (clear refusal, request not executed). The one gap is not describing the returned metrics format/payload.

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 endpoint and resource are front-loaded, followed by the auth requirement and failure behavior. The trailing note about the path being hand-added is meta-context rather than invocation guidance, but it is compact and arguably useful.

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 zero-parameter, annotation-free, output-schema-free tool, the description covers the essentials: what it returns (Prometheus metrics), how to authenticate, and what happens on missing credentials. Only the response format is left implicit.

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 tool takes zero parameters, so per the baseline the schema fully covers inputs. The description adds nothing about parameters because there are none to describe, which is appropriate.

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 endpoint (GET /metrics) and resource (Prometheus metrics), which is concrete and identifiable. It doesn't explicitly contrast with siblings like system_get_stats or system_get_nodes_metrics, but the endpoint scope is unambiguous.

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?

It states the auth prerequisite (Basic-auth with REMNA_METRICS_USER/REMNA_METRICS_PASS) and the behavior when credentials are absent, which is real usage context. However, it never says when an agent should prefer this over the sibling system_* metrics tools, so alternative selection is left to inference.

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