Bolna → Slack call-end notifier

A small Flask webhook service that posts a Slack alert every time a Bolna voice-AI call ends. Pure-Python deps only — runs on Python 3.10+ including 3.14. The alert includes the four fields requested:

• id — the execution / call ID
• agent_id — the Bolna agent that handled the call
• duration — conversation_duration from the Bolna payload, formatted as Xm Ys
• transcript — the full transcript (truncated in Slack to keep messages readable)

How it works

Bolna agent finishes a call
        │
        ▼
Bolna POSTs the execution payload to /bolna/webhook
        │
        ▼
This service extracts id / agent_id / conversation_duration / transcript
        │
        ▼
POSTs a formatted message to the Slack Incoming Webhook

Bolna's Analytics tab webhook delivers the same payload as the Get Execution API. Only calls whose status is in NOTIFY_STATUSES trigger an alert — by default the terminal statuses (completed, call-disconnected, failed, no-answer, busy, canceled, stopped, error).

Setup

1. Create a Slack Incoming Webhook

Follow the Slack docs to create a Slack app, enable Incoming Webhooks, and add one to the channel you want alerts in. Copy the generated https://hooks.slack.com/services/... URL.

2. Configure and run the service

git clone <this-repo>
cd bolna
python -m venv .venv && source .venv/bin/activate
pip install -r requirements.txt
cp .env.example .env
# edit .env and paste your SLACK_WEBHOOK_URL
python app.py

The service listens on http://0.0.0.0:8000 by default and exposes:

Method	Path	Purpose
GET	/healthz	Liveness check
POST	/bolna/webhook	Receives Bolna execution payloads

3. Expose it publicly

Bolna needs a publicly reachable HTTPS URL. For local testing use ngrok:

ngrok http 8000
# -> https://<id>.ngrok-free.app

4. Point Bolna at your endpoint

1. Open your Bolna agent (you can clone the template agent d311e737-70e6-4075-bef6-c0ef3a7026b4).
2. Go to the Analytics tab.
3. Paste https://<your-public-host>/bolna/webhook into "Push all execution data to webhook".
4. Save the agent.

If you set WEBHOOK_SECRET in .env, also append ?secret=<value> to the URL (or have Bolna send an X-Webhook-Secret header if your plan supports custom headers). Bolna's docs note that requests originate from 13.203.39.153, which you can additionally allowlist at your network layer.

5. Make a test call

Trigger any call on that agent. When it ends you should see the message land in Slack within a couple of seconds.

Configuration

All config lives in .env (see .env.example):

Variable	Default	Description
SLACK_WEBHOOK_URL	required	Slack Incoming Webhook URL
WEBHOOK_SECRET	empty	If set, required as X-Webhook-Secret or ?secret=
NOTIFY_STATUSES	completed,call-disconnected,failed,no-answer,busy,canceled,stopped,error	Comma-separated statuses that trigger an alert
HOST / PORT	0.0.0.0 / 8000	Bind address

Local end-to-end test without Bolna

You can simulate a Bolna webhook with curl:

curl -X POST http://localhost:8000/bolna/webhook \
  -H 'Content-Type: application/json' \
  -d '{
    "id": "5f7a3e0c-1c4e-4f30-9c52-7b8a1f2d4e10",
    "agent_id": "d311e737-70e6-4075-bef6-c0ef3a7026b4",
    "conversation_duration": 73.4,
    "status": "completed",
    "transcript": "agent: Hello, this is Bolna.\nuser: Hi, Id like to book a table."
  }'

Tests

pip install pytest
pytest -q