sys_health

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

With no annotations provided, the description carries the full burden. It discloses the tool's scope (checking binaries, config, backend, VMs) and implies a read-only health check, but it doesn't state whether it has side effects, how long it might take, or what the output format is. The description is honest but not deeply transparent about behavior beyond the listed checks.

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?

Two sentences, no filler. The first sentence lists the full scope of checks, and the second delivers a clear directive. Every word earns its place.

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-argument health-check tool, the description is nearly complete: it tells the agent what will be checked and when to run it. It doesn't describe the return format or how to interpret results, but with no output schema and no annotations, a brief note on what the output contains would push it to 5. Still, the core context for invoking it correctly is present.

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 and the schema already states 'Tool without arguments.' The description adds no parameter-specific meaning because there are none to document. Baseline 4 for zero params 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 uses a specific verb ('Check') and names the exact resources: binaries, config, backend capabilities, and every VM's power, guest SSH port, and debugger transport on the host. It clearly distinguishes itself from sibling tools like sys_state or vm_state by covering a broader health-check scope.

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 phrase 'Run this first' explicitly tells the agent when to use this tool, establishing it as the initial diagnostic step before other operations. This is strong usage guidance, though it doesn't explicitly name alternatives or exclusions, the directive is unambiguous.

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