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

Annotations already cover readOnly (safe read) and idempotent. The description adds the cost and the daily granularity, which is useful. However, it does not explain what 'stress scores' represent, how many data points are returned, or the default time range when 'from'/'to' are omitted. With annotations present, the bar is lower, and this is adequate but not rich.

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 a single sentence that front-loads the cost and states the core functionality. It is concise and free of filler, though it omits usage guidance. Its brevity is a plus, but the lack of context holds it back from a 5.

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 simple read-only tool with 3 parameters and no output schema, the description provides enough to call it correctly. However, it does not clarify the semantics of 'stress scores' or the behavior when 'from'/'to' are absent, and it does not differentiate from sibling capacity tools. This is a moderate 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?

Schema description coverage is 100%, so all parameters (gpu, from, to) are already documented with formats and an example for gpu. The description adds no parameter-specific meaning beyond the schema, so the baseline of 3 applies.

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 resource (GPU model) and the metric (daily capacity stress scores). The word 'history' implies a time series, distinguishing it from siblings like 'capacity_stress' without naming them explicitly. It is specific but not perfectly differentiated.

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?

No guidance is given on when to use this tool versus sibling tools such as capacity_stress or capacity_headline. The only extra information is a cost warning (0.05 USDC per call), which is not usage guidance. The agent must infer the historical scope from the name.

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