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

Annotations declare readOnlyHint=true, so the read safety is covered. The description adds meaningful behavioral context beyond that: the scoring scale (Extreme/Severe/Moderate/Minor), hourly update cadence, 10-year history, and interpretation thresholds (mean ~30, 60+ elevated). This enriches the agent's understanding without contradicting 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?

The description is dense but every sentence earns its place: the first defines the output and scoring, the second lists concrete use cases, and the final fragment notes update frequency. It is front-loaded with the core purpose and contains no filler.

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 one optional parameter and no output schema, the description is highly complete: it names the return fields, gives the scoring formula, describes the history option indirectly through the schema, and states update frequency. Minor gaps like the exact structure of history results are not critical given the simplicity.

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 schema description covers the single optional 'days' parameter completely (100% coverage), including behavior, limits, and the Gold tier caveat. The description itself adds no parameter-specific detail, but the schema does all the heavy lifting, so the baseline 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 returns a 0-100 US severe-weather hazard load score, with a severity-weighting formula and specific output fields (hazard_load_score, extreme_alerts, severe_alerts). This is a specific verb+resource with enough detail to stand apart from any sibling weather tool.

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 provides explicit when-to-use guidance: storm severity, weather alerts/warnings, tornado/hurricane risk, national weather disruption, and logistics/routing/event decisions. However, it does not mention when not to use it or name alternative tools, so it stops short of the full 5.

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