API & MCP

Everything a person can do on Focus Room World Clock, a program or AI agent can do with the same inputs and get the identical result.

HTTP API

POST https://focusroomworldclock.usefulweb.app/api/v1/calculate – run Focus Room World Clock
GET https://focusroomworldclock.usefulweb.app/api/v1/tool – inputs, output schema, examples
OpenAPI 3.1: /openapi.json · /openapi.yaml
Errors: application/problem+json; 422 includes per-field errors.

Focus Room World Clock

Shows one moment on the clocks of up to twelve time zones — local date and time, weekday, UTC offset, daylight saving and the day difference — as a table and as analogue clock faces, then plans a meeting: for each hour of the day it lists how many places are inside their working hours, so you can see at a glance when everyone is at work. The Focus Room app shows the same clocks as a live world-clock strip.

Inputs of Focus Room World Clock
Field	Type	Default	Description
`zones`	list	["Europe/Berlin","America/New_York","Asia/Tokyo"]	Time zones. One IANA name per line; the first one is the reference for day differences and the meeting planner.
`at`	datetime	—	Moment (optional). Empty = now (rounded down to the minute).
`atZone`	text	"UTC"	Time zone of that moment. IANA time-zone name such as Europe/Berlin, America/New_York, Asia/Kolkata or UTC.
`workStart`	integer	9	Working hours start
`workEnd`	integer	17	Working hours end

Example request

Berlin, New York and Tokyo on a Monday morning in December

curl -X POST https://focusroomworldclock.usefulweb.app/api/v1/calculate -H 'content-type: application/json' -d '{"zones":["Europe/Berlin","America/New_York","Asia/Tokyo"],"at":"2026-12-21T09:00","atZone":"Europe/Berlin"}'

Every result contains

inputs (normalised, defaults applied), summary, result (validated against the published schema), units, assumptions, sources, warnings, computedAt and links.

MCP (Model Context Protocol)

Streamable HTTP endpoint: https://focusroomworldclock.usefulweb.app/mcp – protocol revisions 2026-07-28 (stateless) and 2025-11-25 / 2025-06-18 / 2025-03-26 (initialize handshake).
Tools: focusroom_world_clock
Local stdio connector: node src/mcp-stdio.ts --tool=focusroom-world-clock

{
  "mcpServers": {
    "focusroom-world-clock": { "type": "http", "url": "https://focusroomworldclock.usefulweb.app/mcp" }
  }
}