examplessecond-brain

for one person, across everything they touch

Second Brain

Your assistant across email, calendar, WhatsApp, and the web. Holds the threads you keep losing, surfaces the connections you'd miss, consolidates its memory overnight so what matters stays close.

second-brain

08:14

i'm back — where was i on everything?

08:14

🧠memory3 active topics · last reflection 2 nights ago
📧email47 unread · 4 threads waiting on you
📅calendarthis week — 2 deadlines, 6 meetings
📝reflectionsconsolidation flagged 2 stalled threads

Welcome back.

**Active**
· *Atlas migration* — you'd just decided to push the cutover to Q3; draft memo at /memory/topics/atlas.md, last edit before you left.
· *Hiring* — second-stage with Kira on Friday; the three areas to probe are in the topic note.
· *The longform piece* — 3 paragraphs from 9 days ago, untouched since.

**Waiting on you**
· Reply to the Q2 doc thread — meeting Thursday.
· Sarah's intro to the design candidate.
· Two vendor follow-ups, neither urgent.

**This week**
· Atlas decision memo due Wed; performance reviews Fri.
· From two consolidations ago: you've twice mentioned wanting to order the Davenport book but haven't. Want me to surface that next time you're at a laptop?

4 sources synthesized · all of this is your own

The situation

You have a person you've been meaning to follow up with, somewhere between an email thread, two WhatsApp messages, and a calendar event next week. You had an idea three weeks ago you've half-forgotten. Your inbox accumulates faster than you triage it. Second Brain runs alongside you across all those surfaces, builds memory of what matters, surfaces it when timing's right, and consolidates what it learns every night.

How it behaves

One agent that runs alongside you, across email, calendar, WhatsApp, and the web.

Pick up where you left off — 'where was i on everything?' or 'what did i think about X?' Pulls memory, recent reflections, and the four extensions into one answer grounded in your own past thinking
Daily check-in — negotiates a time with you on first run, then fires each morning already knowing what's on today and what landed overnight
Overnight memory consolidation — single-shot reflection task hardcoded in the blueprint. It compresses, spots patterns, and surfaces recovered thoughts when timing fits
Chat is the interface — no dashboards to maintain, conversation is the surface, memory accumulates underneath

One agent, four extensions, two schedules. The agent picks when its daily check-in fires, to fit your rhythm. You set the nightly memory consolidation, so the agent can't quietly skip its own housekeeping.

What stays separate

Every external read or write is an approval gate provided by the extension framework. Email reads prompt, calendar writes prompt, WhatsApp sends are off by default, web fetches gate by domain. The container network is sdk-only, so the agent can't dial out around the extensions. The only routes off your machine are the ones you wired. The 'second brain' stays yours: nothing leaves without an approval you saw.

What's in the box

Extensions	email, calendar, whatsapp, web-fetch
Transports	web, cli
Scheduled jobs	nightly memory consolidation pass (locked in blueprint), and a daily check-in cadence the agent negotiates with you on first run
Blueprint highlight	One agent, four extensions, agent-scheduled daily check-in, blueprint-locked nightly memory consolidation on a single-shot reflection channel

Build it yourself

Install Cast, then describe this in the admin chat. The Design agent writes the agents, conversations, and ACL for you. The extensions you'd need are listed above.