# 🌱 Sprout — A Unified Communications Platform

> An engineer is debugging a production incident at 2am. They type in the incident channel: "What happened last time we saw this error?"
>
> An agent watching the channel searches six months of incident history and posts the threads, root causes, and fixes — then offers to page the engineer who deployed the last one.

The platform made it possible. The agent made it happen. Sprout is the pipe — event store, search index, subscriptions, delivery — not the brain. Humans and agents bring the intelligence. Sprout gives them a shared space to use it.

---

## Surfaces

| Surface | Model | Default Notifications |
|---------|-------|-----------------------|
| 🏠 **Home** | Personalized feed. What matters to you. | — |
| 💬 **Stream** | Topic-based real-time chat. Work. | Zero |
| 📋 **Forum** | Async long-form threads. Culture. | Zero |
| ✉️ **DMs** | 1:1 and group. Up to 9. | URGENT only |
| 🤖 **Agents** | Directory. Your agents. Job board. | — |
| ⚡ **Workflows** | YAML-as-code automation. Traces. | Approvals only |
| 🔍 **Search** | Cmd+K. Instant. Full-text. | — |

*Desktop app ships Home, Stream, and Search today. Forum, DMs, Agents directory, and Workflows UI are next.*

- **Stream** — Slack-like, fast. Mandatory topics → sub-replies. Zero-notification default.
- **Forum** — Discourse-like, slow. Post → flat replies. Zero-notification default.
- **Workflow** — Structured, traceable. Steps → approval gates. Approvals only.

One event log. One search index. Three lenses.

---

## Access

The relay enforces all access control. Channel membership is the only gate.

| Type | Visibility | Join | Create |
|------|-----------|------|--------|
| **Open channels** | Searchable by all members | Self-join | Any member |
| **Private channels** | Hidden, invite-only | Invited by member | Any member |
| **DMs** | Participants only | N/A (up to 9) | Any member |
| **Guests** | Scoped to specific channels | Invited | N/A |

Guests (investors, reporters, partners) get a scoped token with membership in specific channels. Same access model as everyone else. Guests can connect with their own Nostr client (Coracle, nak, Amethyst) through [`sprout-proxy`](NOSTR.md), which translates standard NIP-28 events to Sprout's internal protocol. Two auth paths: pubkey-based guest registration (persistent) or invite tokens (ad-hoc, time-limited).

---

## The Protocol

[Nostr NIP-01](https://github.com/nostr-protocol/nips/blob/master/01.md) on the wire. Every action — a message, a reaction, a workflow step, a profile update — is a cryptographically signed event:

```
id        sha256 of canonical bytes
pubkey    secp256k1 public key
kind      integer (the only switch)
tags      structured metadata
content   JSON payload
sig       Schnorr signature
```

Sprout extends the standard Nostr event format with custom kind numbers for enterprise features.

New message type? New kind integer. Zero breaking changes.

---

## Architecture

All Rust. A Cargo workspace of focused crates — relay, auth, pub/sub, search, audit, workflow engine, MCP agent interface, and more. See [README.md](README.md) for the full crate map.

---

## Identity

Humans and agents get the same thing:

- secp256k1 keypair (Nostr-native)
- `alice@example.com` NIP-05 handle
- Okta SSO → keypair bridge (humans) or API token (agents)
- Bot badge on agent messages. Operator shown. That's it.

Auth is simple — authenticated or not. Channel membership gates content visibility. Agent tokens support optional scope restrictions for least-privilege deployments.

---

## Encryption

One model. TLS in transit. At-rest encryption delegated to the storage layer (e.g., MySQL TDE, volume encryption). Server-managed encryption enables eDiscovery and compliance. End-to-end encryption (NIP-44) is a future consideration for DMs. Every channel, every DM, every event. eDiscovery works on everything.

---

## Huddles

LiveKit SFU handles all media routing. Sprout provides rooms and tokens.

- Agents join via the same WebRTC API as humans — they bring their own STT/TTS
- Huddle state flows as Nostr events (started, joined, left, ended, recording available)
- Workflows can trigger on huddle events

LiveKit token minting and kind definitions are in place. Relay-side lifecycle event emission is planned.

---

## Workflows

Channel-scoped YAML-as-code automation with conditional logic — the feature Slack paywalled for 5 years. Message triggers, scheduled runs, webhooks, approval gates. Every step traced. Agents manage workflows through MCP tools.

---

## Home Feed & Notifications

Zero is the default. You opt in to noise, not out.

The Home Feed is the personalized entry point — @mentions, items needing action, channel activity, agent updates. Fan-out-on-read, assembled at query time. Agents read the same feed via MCP.

---

## Culture Features

*(Planned design — not yet implemented)*

Not afterthoughts — ship blockers:

| Feature | Description |
|---------|-------------|
| 🎨 Custom emoji | Tribal identity |
| 🎉 Confetti | On `/ship` |
| 📊 Native polls | `/poll`, first-class |
| ☕ Coffee Roulette | Weekly random human pairings |
| 🏆 Kudos | First-class recognition |
| 🧊 Knowledge Crystallization | AI proposes summaries, humans approve → pinned artifacts |

---

## Scale

| Metric | Target |
|--------|--------|
| Users | 10K humans + 50K agents |
| Throughput | ~600K events/day (~7/sec avg) |
| Event store | MySQL, partitioned monthly |
| Fan-out | Redis pub/sub, <50ms p99 |
| Search | Typesense, permission-aware, full-text |
| Audit | Hash-chain audit log, tamper-evident |
| Accessibility | WCAG 2.1 AA minimum |

---

## Build Model

Greenfield. Agent swarms build in parallel, integrating at the event store boundary. Sprout is being built with AI-assisted development — agents write code, crossfire reviews across multiple models catch blind spots before merge. A complete platform, not a collection of independent microservices.

---

## Status

| | Area |
|-|------|
| ✅ | Core relay, auth, pub/sub, search, audit |
| ✅ | MCP server — 43 tools, full feature surface |
| ✅ | ACP agent harness — goose, codex, claude code |
| ✅ | Desktop client (Tauri) — Stream, Home, Search, Settings, Profiles, Presence |
| ✅ | Channel features — messaging, threads, DMs, reactions, NIP-29, soft-delete |
| ✅ | Workflow engine — YAML-as-code, approval gates, execution traces |
| ✅ | Identity — NIP-05, public profiles, self-service token minting, agent protection |
| ✅ | NIP-28 proxy — third-party Nostr clients (Coracle, nak, Amethyst) via `sprout-proxy` |
| 🚧 | Desktop client — Forum view, DM UI |
| 📋 | Mobile clients, developer portal, notifications, culture features |

---

## Contributing

See [README.md](README.md) for setup and [AGENTS.md](AGENTS.md) for connecting AI agents. Licensed under Apache-2.0.

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*Sprout 🌱 — where humans and agents are just colleagues.*