Cynthia

A personal capture system that lets you drop thoughts/tasks into Slack (text or voice), automatically classifies and files them to Notion, sends you digests, and allows corrections via reply.

• Text capture — Send messages to Slack, auto-filed to Notion
• Voice capture — Send voice notes, transcribed via Whisper and filed
• Smart classification — GPT-4o-mini routes to Tasks, Work, People, or Admin
• Priority detection — "urgent" → P1, casual → P3
• Follow-up questions — Bot asks for clarification on vague captures
• Fix flow — Reply fix: work to reclassify
• Morning planning — 9:30am GMT digest with priorities
• Evening review — 8pm UTC summary
• Weekly review — Sunday 3pm UTC deep dive
• On-demand review — /review command anytime

Slack (text/voice) → Vercel API → OpenAI (classify/transcribe) → Notion
                         ↓
                   Slack (confirm + follow-up)

Create these 5 databases in Notion:

Tasks Database

Work Database

People Database

Admin Database

Inbox Log Database

Get each database ID from the URL: notion.so/DATABASE_ID?v=...

1. Create app at https://api.slack.com/apps
2. OAuth & Permissions — Add scopes:
   • channels:history
   • channels:read
   • chat:write
   • files:read
   • im:write
   • commands
3. Event Subscriptions — Enable and set URL to:

   https://your-app.vercel.app/api/slack/events
   

4. Subscribe to bot events:
   • message.channels
   • file_shared
5. Slash Commands — Create /review:
   • Command: /review
   • URL: https://your-app.vercel.app/api/slack/commands
6. Install to workspace
7. Create a private channel (e.g. #cynthia) and invite the bot

Create .env.local locally or add to Vercel:

# Slack
SLACK_BOT_TOKEN=xoxb-your-bot-token
SLACK_SIGNING_SECRET=your-signing-secret
SLACK_INBOX_CHANNEL_ID=C0YOUR_CHANNEL_ID
SLACK_USER_ID=U0YOUR_USER_ID

# Notion
NOTION_API_KEY=ntn_your_api_key
NOTION_TASKS_DB_ID=your_tasks_db_id
NOTION_WORK_DB_ID=your_work_db_id
NOTION_PEOPLE_DB_ID=your_people_db_id
NOTION_ADMIN_DB_ID=your_admin_db_id
NOTION_INBOX_LOG_DB_ID=your_inbox_log_db_id

# OpenAI
OPENAI_API_KEY=sk-your-openai-key

# Cron (generate a random string)
CRON_SECRET=your-random-secret

# Install dependencies
yarn install

# Deploy to Vercel
vercel --prod

# Add env vars to Vercel
vercel env add SLACK_BOT_TOKEN production
# ... repeat for all env vars

# Redeploy to pick up env vars
vercel --prod

Send messages to your Slack channel:

Voice notes work the same — just record and send.

In Notion, change the Status field to Done. Item won't appear in future digests.

# Run locally
yarn dev

# Test Slack webhooks locally (use ngrok)
ngrok http 3000
# Update Slack app URLs to ngrok URL temporarily

• Runtime: Node.js + TypeScript
• Framework: Next.js 14 (App Router)
• Hosting: Vercel
• Storage: Notion
• AI: OpenAI (GPT-4o-mini, Whisper)
• Messaging: Slack