noaa-tidesandcurrents-mcp

Get Marine Text Forecast (NWS)

nws_get_marine_forecast

Read-onlyIdempotent

Get the official NWS Coastal Waters Forecast narrative for a latitude/longitude marine zone, including wind/seas text and Small Craft Advisories for US coastal waters.

Instructions

Get the official NWS Coastal Waters Forecast (CWF) narrative for the marine zone covering a latitude/longitude — day-part wind/seas text ("SE winds 10 to 15 kt... Bay waters choppy"), including Small Craft Advisories.

The point must lie in (or very near) US coastal waters; CWF zones extend roughly 20-60 NM offshore. Returns the zone's segment from the latest bulletin plus the office-wide synopsis.

For numeric hourly wind values use nws_get_wind_forecast; for observed wind at a NOAA station use noaa_get_meteorological_data (product "wind").

Input Schema

TableJSON Schema

Name	Required	Description	Default
`latitude`	Yes	Latitude in decimal degrees (-90 to 90).
`longitude`	Yes	Longitude in decimal degrees (-180 to 180).
`response_format`	No	Output format: "markdown" for a readable summary table, "json" for the complete structured payload.	markdown

Output Schema

TableJSON Schema

Name	Required	Description	Default
`_response`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Addedv1.0.1Oct 5, 2026

TDQS

A4.4/5.0

Behavior4/5

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

Annotations already declare readOnly, idempotent, non-destructive, openWorld. The description adds genuinely useful context beyond them: the ±20-60 NM offshore domain constraint and the fact that the return includes the zone segment plus the office-wide synopsis and Small Craft Advisories.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three tight sentences, front-loaded with the core action and sample output, followed by constraints and routing. Every sentence earns its place, though the sample quote is slightly decorative.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With an output schema present, the description needn't explain return values, yet it briefly notes what is returned (zone segment + synopsis). Coverage of purpose, domain constraint, and alternatives is sufficient for correct invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so latitude, longitude, and response_format are already fully documented in the schema. The description adds no extra parameter syntax or format detail, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb ('Get'), resource ('official NWS Coastal Waters Forecast (CWF) narrative'), and scope ('for the marine zone covering a latitude/longitude'). It even quotes sample content, distinguishing it from sibling forecast tools at a glance.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives explicit routing: 'For numeric hourly wind values use nws_get_wind_forecast; for observed wind at a NOAA station use noaa_get_meteorological_data (product "wind").' It also states the geographic precondition (point must lie in or near US coastal waters, 20-60 NM offshore).

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