Documentation

Everything you need to get started with SecondBrain.

Quick Start

Get up and running with SecondBrain in under five minutes. No configuration required.

1

Create your account

Sign up at second-brain.io with your email address. No credit card required for the free plan.

2

Connect your Slack workspace

Click "Add to Slack" in your dashboard Settings page. Authorize SecondBrain to access your workspace.

3

Create the #sb-inbox channel

Create a new channel called #sb-inbox in your Slack workspace. This is where you'll capture thoughts. SecondBrain will automatically detect it.

4

Send your first capture

Type anything into #sb-inbox. Try something like: "Need to follow up with Sarah about the Q2 proposal." That's it — just type naturally.

5

Check your dashboard

Head to your SecondBrain dashboard. Your capture has been automatically classified into People, Projects, Ideas, or Admin. You'll also see the AI's confidence score for the classification.

How Classification Works

The 4 Categories

SecondBrain classifies every capture into one of four categories:

People

Relationships, conversations, follow-ups, and context about people in your life.

Projects

Active work with deadlines and next actions. Things that need to move forward.

Ideas

Thoughts without deadlines. Creative sparks, observations, and possibilities.

Admin

Tasks and logistics. Appointments, renewals, errands, and life maintenance.

Confidence Scores

Every classification comes with a confidence score between 0 and 1. This tells you how certain the AI is about its decision.

0.8 - 1.0 (High)Filed automatically with full confidence
0.6 - 0.8 (Medium)Filed but flagged for review
Below 0.6 (Low)Not filed — asks you for clarification

Correcting a Misclassification

If the AI gets it wrong, simply reply to the confirmation message in Slack with a correction:

fix: Projects not People

The entry will be moved to the correct category instantly. The system also learns from your corrections, improving future classifications for similar content.

Capture Channels

SecondBrain lets you capture from the tools you already use. No app switching, no friction.

Slack

Available

Primary capture channel. Create a #sb-inbox channel and type naturally. Supports text, links, and file attachments.

Web Dashboard

Available

Capture directly from your SecondBrain dashboard using the quick-capture input. Available on desktop and mobile browsers.

Email Forwarding

Coming Soon

Forward any email to your unique SecondBrain address. The system will extract key information and classify it automatically.

Telegram Bot

Coming Soon

DM the SecondBrain bot on Telegram for mobile-first capture. Text, voice messages, and images supported.

WhatsApp

Coming Soon

Send captures via WhatsApp for quick, on-the-go knowledge capture.

API

Available

Build custom integrations using the SecondBrain API. Perfect for developers who want to pipe data from their own tools.

Daily Digest & Weekly Review

Daily Digest

Every morning at 8 AM (configurable), you receive a concise digest via Slack DM. Under 150 words, it covers:

  • Top 3 action items for today
  • Follow-ups that are due or overdue
  • Blocked projects that need attention
  • One win from yesterday for motivation
Example Daily Digest

Good morning. Here's your focus for today:

1. Follow up with Lisa at Acme Corp about the proposal (due Friday)

2. Review Q2 budget projections (3 days since last update)

3. Schedule dentist appointment (overdue)

Yesterday's win: Completed the onboarding redesign.

Weekly Review

Every Sunday at 4 PM (configurable), you receive a weekly synthesis. Under 250 words, it covers:

  • Summary of captures and classifications for the week
  • Open loops that need closing
  • People you haven't followed up with
  • Patterns the AI noticed in your captures
  • Suggested focus areas for next week

Customization

You can customize digest timing, delivery channel, and content preferences from Settings > Notifications in your dashboard. Options include changing delivery time, choosing between Slack DM or email delivery, and selecting which sections to include.

API Reference

The SecondBrain API lets you build custom integrations. All endpoints require authentication via API key.

Authentication

Generate an API key from Settings > API in your dashboard. Include it in the Authorization header:

// Include in all API requests
Authorization: Bearer sb_your_api_key_here

Capture Endpoint

POST /api/v1/capture
// Request body
{
"text": "Need to follow up with Sarah about Q2",
"source": "api"
}
// Response
{
"id": "cap_abc123",
"category": "people",
"confidence": 0.91,
"created_at": "2026-02-14T10:30:00Z"
}

Query Endpoints

GET /api/v1/people
GET /api/v1/projects
GET /api/v1/ideas
GET /api/v1/admin
GET /api/v1/inbox?limit=50&offset=0

All query endpoints support ?limit, ?offset, and ?search query parameters for pagination and filtering.

Rate Limits

Free plan100 requests/hour
Pro plan1,000 requests/hour
Team plan5,000 requests/hour

Need help?

Check the Help Center for FAQs or reach out to our support team.