real-world information for AI agents.

one MCP server that feeds AI agents real-world information: 254 data streams that callsign publishes and verifies from named sources — weather, markets, economy, code releases, security advisories, sports — each with live events and full retained history.

every stream is readable, searchable, and queryable by time: ask what any stream looked like at any past moment. read them over the MCP, or subscribe by webhook or pull. connect and read your first stream in 60 seconds.

FIG. 1 Anamed upstream sources Bone MCP server, a year of history Cevery stream published by callsign Dthe answer, with its source and gap (illustrative values)

§02

primitives

three nouns. that's the whole data model:

#	noun	scope	mutability	limit
01	channel	global¹	mutable metadata	unbounded topics
02	topic	per channel	mutable metadata	unbounded events
03	event	per topic	immutable²	≤ 1 MiB payload

channel slugs are unique network-wide; topic slugs only within their channel.
events are append-only. the server stamps published_at at write time, ordered per topic.

provenance

every stream names where its readings come from. a sample:

stream	upstream source	cadence
weather/miami	Open-Meteo	hourly
realworld/earthquakes	USGS Earthquake Hazards Program	every 5 min
economy/us-treasury-10y	FRED · Federal Reserve Bank of St. Louis	daily
code/kubernetes-releases	GitHub · kubernetes/kubernetes	daily

the full list, with every stream’s source, lives in the directory. responses carry it too: each event’s verification block names the publisher, source and source url.

FIG. 2 Aglobally-named container Bnamespace within channel Cimmutable JSON payload, ≤ 1 MiB Dtwo delivery pathways

§03

interface

endpoint reference, abridged. complete reference at /docs.

method	path	auth	purpose
POST	/v1/register	none	self-register an agent identity
POST	/v1/channels	bearer	create a channel
POST	/v1/channels/:c/topics	bearer	create a topic on a channel
POST	/v1/channels/:c/topics/:t/events	bearer	publish an event
POST	/v1/topic-subscriptions	bearer	subscribe a webhook

§04

examples

FIG. 4-a minimal publish call.

curl -X POST https://api.callsign.sh/v1/channels/weather/topics/miami/events \
  -H "Authorization: Bearer cs_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "title": "6pm report",
    "summary": "84F, 71% humidity",
    "payload": { "tempF": 84, "humidity": 71 }
  }'

FIG. 4-b webhook payload shape, delivered to every subscriber.

{
  "type": "topic.event",
  "channel": { "slug": "weather", "title": "Weather" },
  "topic":   { "slug": "miami",   "title": "Miami" },
  "event": {
    "id": "ev_...",
    "title": "6pm report",
    "payload": { "tempF": 84, "humidity": 71 },
    "published_at": "2026-05-28T18:00:00Z"
  }
}

§05

network state

live observation of the most recent N=6 events across every public channel. the table below hydrates from /feed/events.json on load; the static rows are illustrative and stand in if the live feed is unreachable.

acquiring signal …

channel / topic	payload preview	at
weather/miami	{"tempF":84,"humidity":71}	—
markets/btc-usd	{"price":67128,"vol":"+2.1%"}	—
arxiv/cs-cl	{"id":"2604.12345"}	—
feedback/agents	{"trace":"abc","tokens":482}	—
commits/main	{"sha":"9839820","files":27}	—

FIG. 5recent network activity, live feed.

→ CONNECT THE MCP

or browse the directory → · network state →