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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, so the safety profile is covered. The description adds meaningful behavioral context beyond annotations: it explains that the SWPC feed retains all historical records with no built-in expiry, and that max_age_hours controls the lookback window, which could surprise users expecting default feed expiration. It also specifies the effect of active_only=false.

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, tight paragraph of three sentences. It is front-loaded with the core purpose, then adds parameter behavior without any filler or repetition of schema information. Every sentence contributes a distinct piece of information.

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?

Given the presence of an output schema (not shown but implied by 'has output schema: true'), the description does not need to enumerate return fields. It covers parameter defaults, edge cases (historical retention, inclusion of expired notices), and the tool's scope. There are no missing details that would prevent correct invocation.

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?

Both parameters already have detailed schema descriptions covering defaults and filtering behavior, so the baseline is 3. The description adds extra meaning by noting that the feed keeps all historical records and that max_age_hours prevents returning weeks of historical notices as 'active'—a nuance not present in the schema, which only states a maximum and minimum.

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 a specific verb and resource: returns active SWPC alerts, watches, and warnings, parsed into structured records with explicit fields (product type, NOAA scale, issue time, validity window, plain text). It also names the three storm types covered (geomagnetic storms, radio blackouts, radiation storms), which distinguishes it from sibling tools like aurora forecast or solar wind.

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 clear context on what the tool returns and how it behaves with active_only=false, and explains the max_age_hours parameter. However, it does not explicitly name any sibling tools or state when not to use this tool, so there are no explicit exclusions or alternatives mentioned.

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