Live Tennis API — Break-Point Starter (Node)

A tiny, runnable app that reacts to break points on the Live Tennis API live feed. It shows exactly where your trading logic goes — and it places no real bets.

It rides the official livetennisapi SDK: it opens the ULTRA WebSocket feed with signals: ['break_point'], routes every frame to a Strategy, and logs the paper action the strategy would take.

Requires an ULTRA key. The WebSocket feed and the break-point signals are ULTRA-tier only. Get a key at https://livetennisapi.com/#pricing.

Needs Node 20+ (for --env-file and the built-in test runner).

Run it

cp .env.example .env          # then put your ULTRA key in .env
npm install
npm start

You'll see output like:

connecting to the live feed with signals=['break_point'] …
BREAK POINT  match=18953  p1 serving, p2 holds 2 break point(s)  swing=0.22
PAPER ORDER  back p2 on match 18953 for 20.00  (2 break point(s) against an unfavoured server)
  -> break point broken  match=18953  p1 win prob now 0.63

Where your code goes

Everything you edit is in strategy.js:

• onBreakPoint(event) — the headline signal lands here.
• decide(event) — return a paper order (or null). Put your edge here.
• placePaperOrder(order) — logs the intended order. Nothing real happens.

Wiring a real venue

placePaperOrder contains a clearly marked block:

// ================= WIRE YOUR OWN EXCHANGE / VENUE HERE =================

The real-execution seam is Strategy._execute. It is left throwing and never called on purpose, so a fresh clone can never move money. To go live, implement _execute against your venue's API and call it from placePaperOrder. That choice — and any risk it carries — is entirely yours.

Test

npm test        # node --test, no dependencies, no network

The tests pump canned frames through the same dispatch path the live app uses, and assert the safety invariant: the execution seam refuses to place a real bet.

How it maps to the API

The subscribe frame this starter sends:

{ "topics": ["live-scores"], "signals": ["break_point"] }

Frames it reacts to: score, break_point, break_point_result. See the WebSocket section of the API reference.

License

MIT — see LICENSE.