get_system_stats

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

No annotations are provided, so the description carries the full burden. It discloses the specific data it returns, and it explicitly notes a limitation ('system stats don't show errors'). It does not explicitly state it's read-only, but the nature of the tool (health snapshot) and lack of parameters makes this clear. It could have added more about potential performance cost or frequency limits, but for a simple read-only tool, this is sufficient.

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 concise and well-structured. It front-loads the core purpose in the first sentence, then provides usage guidance in clearly labeled sections. Every sentence serves a purpose with no redundancy or fluff.

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 tool with no output schema, the description is complete. It explains what the tool does, what data it returns, when to use it, when not to use it, and its limitations. The sibling context further clarifies its position in the API. No additional details are necessary for an agent to select and invoke it correctly.

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 has zero parameters, so the input schema trivially has 100% coverage. The baseline for 0 params is 4, and the description correctly omits any parameter details since there are none. No additional semantics are needed.

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's purpose with a specific verb ('Get') and resource ('BEAM runtime health') and lists the exact metrics returned (memory, scheduler count, process/port/atom counts, uptime, IO throughput). It effectively distinguishes itself from sibling tools like get_app_config, get_process_info, and get_logs.

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 includes explicit WHEN TO USE and NOT FOR sections with named alternative tools (get_app_config, get_process_info, get_logs), providing clear guidance on when to choose this tool over others. This is exemplary usage guidance.

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