DataNarrator

Slack
Dashboard
Story

Inspiration

Working with Tableau dashboards, we noticed a recurring challenge: data visualization is powerful, but not everyone can interpret charts quickly. Executives need summaries, not spreadsheets. Teams need insights shared in Slack, not buried in tabs.

We asked: What if AI could look at your Tableau dashboard and tell you the story behind the data?

That's how DataNarrator was born — an AI-powered companion that transforms Tableau visualizations into compelling narratives.

What it does

DataNarrator connects to your Tableau Cloud site and:

📊 Fetches your dashboards via the Tableau REST API
🤖 Analyzes underlying data using local AI (Ollama/Llama)
📝 Generates data stories in multiple formats:
- Quick Summary (2-3 sentences)
- Executive Brief (metrics + trends + recommendations)
- Deep Dive (comprehensive analysis)
💬 Shares to Slack with one click
🔊 Reads stories aloud using text-to-speech

How we built it

Backend:

Node.js + Express server
Tableau REST API for authentication & data extraction
Ollama (local LLM) for AI story generation
Slack Web API for sharing

Frontend:

React + Vite for fast development
Tableau Embedding API v3 for interactive dashboards
Custom dark theme with glassmorphism design
Web Speech API for voice narration

Challenges we faced

Tableau API Authentication — Getting PAT (Personal Access Token) authentication working required careful handling of the multi-step auth flow.
Data Context for AI — Raw CSV data isn't enough. We had to build summary statistics (min, max, avg, unique values) to give the LLM meaningful context.
Prompt Engineering — Crafting prompts that produce consistent, insightful narratives took multiple iterations.