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

Goes well beyond the readOnly/idempotent/openWorld annotations by disclosing return shape (up to ten qualifying stations plus three with insufficient records, with date-specific coverage and distance) and default date behavior (30 days ending 5 days before today UTC, max 366 days). This is exactly the operational context an agent needs before calling.

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?

Three tight sentences with the use case and scope front-loaded, followed by return behavior and exclusions. No filler or redundancy.

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 annotations covering safety and an output schema covering returns, the description supplies the remaining essentials: trigger conditions, geography limits, and default date window. Nothing needed for correct invocation is missing.

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 coverage is 100%, so the baseline is 3, but the description adds meaning the schema lacks: the implicit date range default and the 366-day ceiling. It does not restate the place format, correctly leaving that to the schema.

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?

States a specific verb and resource — finds reporting weather stations near a US city/ZIP/address — and scopes it to historical weather use. It is clearly separable from the sibling generate_weather_log, which implies producing a log rather than locating stations.

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?

Explicitly frames the triggering intent (weather history, historical data, past weather by ZIP) and gives hard exclusions: no forecasts, no current conditions, no non-US places. It does not name the sibling generate_weather_log as the alternative for log creation, so it falls short of a full 5.

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