EMQX Prometheus Stats

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

The description discloses that the output is raw Prometheus exposition text and that it is large, which are behavioral traits not captured in the annotations. The annotations already cover read-only/idempotent safety, so the description adds useful size and format context.

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 two short sentences with no filler. It states the resource type and a usage recommendation, every word contributes.

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?

With an output schema present, the description needn't detail return format. The annotation covers safety, the schema covers parameters, and the description provides the core purpose and a size warning. For a simple read-only tool, this is sufficient.

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 provides 100% coverage for the single max_bytes parameter, including its purpose and constraints. The tool description does not add any parameter semantics beyond the schema, so baseline 3 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 clearly identifies the tool as returning raw Prometheus exposition text, a specific resource, and differentiates it from sibling emqx_broker_stats by recommending that alternative for large outputs. This gives a specific verb and resource, distinguishing it from siblings.

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 explicitly says 'Large — prefer emqx_broker_stats,' providing a clear when-to-use alternative. This tells the agent to favor the sibling tool for broker stats while implying this tool is for raw Prometheus text.

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