SRE: Host Headroom

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true, so the description does not need to reiterate safety. The description adds that the tool shows CPU and memory side-by-side, which is useful but does not disclose additional behavioral traits beyond what annotations provide.

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 highly concise: two sentences. The first sentence defines the tool's function, and the second provides usage examples. No wasted words; each sentence 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?

The tool is simple with one optional parameter and no output schema. The description fully explains its purpose and usage scenarios. Given the low complexity, it is complete and sufficient for an agent to know when and how to use it.

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?

There is only one parameter 'since' with a description in the schema. The schema coverage is 100%, and the description does not add any extra meaning or usage details beyond the schema. Baseline of 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 states the tool's purpose: an SRE view of host CPU load and memory side-by-side. It provides specific use cases ('which host is hottest', 'where is headroom lowest', 'which VM is nearest saturation'), effectively distinguishing it from sibling tools like host_cpu, host_memory, top_cpu, and top_memory.

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 'Use for' followed by three example queries, providing clear context on when to use the tool. It does not explicitly state when not to use or mention alternatives, but the examples give sufficient guidance for typical scenarios.

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