Retrieve the public text-based weather forecast for a specific National Weather Service zone by providing its zone ID, such as CAZ006 or DCZ001.
Get the public text-based forecast for an NWS forecast zone (e.g. 'CAZ006'). Find the zone ID via nws_point_info.
| Name | Required | Description | Default |
|---|---|---|---|
| zone_id | Yes | Forecast zone ID, e.g. 'CAZ006', 'DCZ001' |
Changes observed during successful MCP inspections.
v2026.9.14Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly/openWorld/idempotent/non-destructive, so the safety burden is covered. The description adds that the forecast is public, text-based, and zone-scoped. It doesn't describe response shape or format details, but for a read-only lookup this is acceptable.
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?
Two tight sentences: purpose first, prerequisite second. No filler or redundant restatement of the schema.
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 one-parameter read-only forecast lookup, the description covers purpose, parameter source, and output nature. It could mention alternatives like nws_forecast for point-based forecasts, but nothing essential 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?
The schema already fully documents zone_id with a description and example (100% coverage). The description adds the useful hint that the zone ID can be found via nws_point_info, but it doesn't need to compensate for any schema gap.
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 ('Get'), resource ('NWS forecast zone'), and output type ('public text-based forecast'). The example zone ID and pointer to nws_point_info reinforce scope. It doesn't explicitly contrast with sibling forecast tools, but the zone-scoped text forecast is distinct enough.
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 instructs the agent to obtain the zone ID via nws_point_info, giving a clear prerequisite and routing cue. It doesn't enumerate when to prefer this over nws_forecast or nws_forecast_hourly, but the context is clear enough for selection.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.