Key, bridge, phone. Then a message.
Run these in order. Your first bridge is free for 7 days with a card on file, nothing charged until the trial ends.
Create an API key at Dashboard → API keys. It starts with sk_ and is shown once, so copy it now. Every call below sends it as Authorization: Bearer $WA_API_KEY.
customer_ref = sandbox. Skip steps 2 and 3, use sandbox wherever a customer_ref appears below, and send to 15550001234, a fake contact who replies within seconds. Events show on your dashboard.pip install requests flask
export WA_API_KEY="sk_..."
Your first bridge is created from the dashboard: one click connects a number and starts the 7-day free trial (card on file, $0 today). Every API call below can address it as /api/instances/default/…: default always means your first bridge, so no name goes in the URL. The call here is how you add more bridges to the subscription.
customer_ref is your internal identifier (user ID, slug, anything you control). webhook_url is optional: leave it out to use the hosted inbox and read events on the dashboard, change it any time with PATCH.
Store the webhook_secret that comes back. It signs every webhook the bridge sends you.
402 no_subscription: connect a number in the dashboard first.import os
import requests
API_KEY = os.environ['WA_API_KEY']
BASE = 'https://wabridges.com/api'
HEADERS = {'Authorization': f'Bearer {API_KEY}'}
def provision(customer_ref, webhook_url):
r = requests.post(f'{BASE}/instances', json={
'customer_ref': customer_ref,
'webhook_url': webhook_url,
}, headers=HEADERS)
r.raise_for_status()
return r.json() # { 'id', 'customer_ref', 'state' }
bridge = provision('user-123', 'https://yourbackend.com/hook')
print(bridge)
{"id": "7d09aa9c-…", "customer_ref": "user-123", "state": "running", "created_at": 1777180605, "webhook_secret": "whs_…", "webhook_url": "https://…/hook"}
You need the phone in hand for this step. Request a pairing code, open WhatsApp on the phone, go to Linked Devices → Link a device → Link with phone number, then enter the code. Any number works, personal, VoIP, or a spare SIM. No phone? Use sandbox.
Once paired, the bridge fires a connected webhook event. Poll /proxy/status or wait for the event.
def pair(customer_ref, phone):
r = requests.post(
f'{BASE}/instances/{customer_ref}/proxy/pair',
json={'phone': phone},
headers=HEADERS
)
r.raise_for_status()
return r.json()['code'] # "ABCD-EFGH"
code = pair('user-123', '15550001234')
print(f'Enter this code on the phone: {code}')
{"code": "ABCD-EFGH"}
Add an Idempotency-Key: <unique-per-message> header in production so a timeout plus retry can never double-send. See Idempotency.
A bridge that sat for a few hours with no phone linked is paused to save resources. The first call after that returns 503 bridge_starting with a Retry-After header. Wait those seconds and retry once.
def send_text(customer_ref, to, body):
r = requests.post(
f'{BASE}/instances/{customer_ref}/proxy/send/text',
json={'chat': to, 'body': body},
headers=HEADERS
)
r.raise_for_status()
return r.json() # { 'message_id', 'timestamp' }
send_text('user-123', '15559876543', 'Hello from the API!')
{"message_id": "ACE41E...", "timestamp": 1777180605}
Inbound messages and events are delivered by POST to your webhook_url. Return 200 immediately and do the work afterwards.
The webhook guide has every event type and field, plus signature verification.
from flask import Flask, request
import threading
app = Flask(__name__)
def handle(payload):
if payload.get('event') == 'message' and not payload.get('from_me'):
print(f"{payload['name']}: {payload['body']}")
@app.route('/hook', methods=['POST'])
def webhook():
payload = request.get_json()
threading.Thread(target=handle, args=(payload,)).start()
return '', 200
Next
Everything the quickstart skipped: media, polls, contacts, presence, and every webhook payload.