system_info

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered elsewhere. The description contributes the scope of the snapshot (which subsystems are sampled), but says nothing about cost, freshness, sampling window or privilege requirements — modest added value given 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?

A single front-loaded sentence listing the returned metrics with no filler, preamble or redundancy. 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?

With zero parameters, full annotation coverage and an output schema, the description only needs to say what the snapshot contains — which it does. The only missing piece is routing guidance against similar read tools, which is a usage concern rather than a completeness gap.

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 there is nothing for the description to disambiguate; baseline 4 applies. The enumerated metric list aligns cleanly with the parameterless contract.

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 enumerates exactly which machine metrics are returned (OS, kernel, uptime, CPU, load, memory, swap, disk), which is a specific resource list rather than a tautology. It does not, however, distinguish itself from adjacent siblings like server_health, workspace_info or environment_variables, which an agent may also consider for 'tell me about the host' requests.

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?

Usage is only implied: the metric list suggests 'call this when you need host-level resource stats', but there is no explicit when-to-use statement, no exclusions, and no pointer to alternatives such as server_health for service-level health or list_processes for per-process detail.

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