open-signals MCP server

open-signals

Public data, ready for maps and agents. Every reading says where it came from, when it was fetched, and what licence it carries.

open-signals has three parts:

coverage, cadence, the key it needs and its licence. Weather, water, ice, hazards, flights, ships, satellites, energy, emissions, filings, trade and more. It's the list to check before writing yet another fetcher.

• A catalogue of public data sources (catalog/sources.json). Each entry gives the API,

the reading:

• Fetchers for the sources we read today. Each one turns an upstream answer into one shape,

{ "id": "noaa-coops:9063085:2026-10-10", "at": "2026-10-10", "metric": "water_level",
    "value": 2.762, "unit": "ft above LWD",
    "summary": "Lake Erie at Toledo 2026-10-10: mean 2.76 ft above low water datum (…)",
    "place": { "id": "coops-toledo", "name": "Lake Erie at Toledo", "lat": 41.6936, "lng": -83.4723 },
    "fields": { "station": "9063085", "datum": "LWD", "readings": 155 },
    "source": { "id": "noaa-coops", "name": "NOAA CO-OPS water levels", "url": "https://tidesandcurrents.noaa.gov/…",
                "fetched_at": "2026-10-10T19:12:03Z", "license": "public_domain" } }

GeoJSON map layers. There are no runtime dependencies; it needs Node 20 or later.

• Ways in: a CLI, a REST API with an OpenAPI description, an MCP server for agents, and

Use it

A public instance runs at https://open-signals.civops.io (REST under /v1, MCP at /mcp). It serves only public-domain and open sources, holds no upstream keys, and is rate-limited per IP. Try https://open-signals.civops.io/v1/layers/volcanoes?elevated=true.

git clone https://github.com/Civops-Platform/open-signals && cd open-signals   # Node 20+, no npm install needed
alias open-signals='node bin/open-signals.mjs'
open-signals sources fires                     # search the catalogue
open-signals sources --topic water --fetchable
open-signals fetch usgs-earthquakes --min 4.5 --window week
open-signals fetch noaa-coops --coops 8518750   # any CO-OPS station
open-signals fetch open-meteo --lat 41.5 --lng -81.7
open-signals layer water_level                 # GeoJSON
open-signals serve --port 3290                 # REST + MCP

fetch and layer run on your machine with your own keys (NASSAPIKEY, EBIRDAPIKEY). The CLI prints each source's licence so you know what you may do with what you fetched.

REST

CESMII i3X

The same layers are served as a read-only CESMII i3X 1.0 endpoint at https://open-signals.civops.io/i3x/v1. The address space has a root, one folder per layer, and one object per place or event. Each object's value is its latest reading (value, quality, timestamp) with source and licence, and its history is every reading held for that place. Subscriptions support sync and server-sent-event streams.

CESMII's conformance suite (build 6, run 10 October 2026) rates it i3X 1.0 Compatible: 50 passed, 0 failed, 10 skipped (report). The skipped tests are the write tests; full compliance needs writes, and a server that republishes public data has nothing to write.

The spec requires authentication on data endpoints, so there is a free public read-only token: os-public-read (send Authorization: Bearer os-public-read). GET /i3x/v1/info needs none.

Static datasets

Shortened. The full README is on GitHub.