> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sint.gg/llms.txt
> Use this file to discover all available pages before exploring further.
# Architecture
> How SINT Protocol, SINT OS, OpenClaw, Avatar, and the products compose into a unified runtime.
SINT Labs ships three conceptual layers: the **Protocol** (authorization substrate), **SINT OS** (the runtime that unifies products), and **the products** themselves (Console, Avatars, Operators, CMO Operator). Each component exists and runs independently. SINT OS is the integration layer that makes them work as one system.
## The unified stack
```
┌─────────────────────────────────────────────────────────────┐
│ SINT OS │
│ │
│ ┌──────────┐ ┌──────────┐ ┌──────────┐ ┌─────────────┐ │
│ │ Avatar │ │ Console │ │ Operator │ │ CMO │ │
│ │ (Face) │ │ (Brain) │ │ (Hands) │ │ (Content) │ │
│ │ 3D+Voice │ │ 31 mods │ │ LinkedIn │ │ 18 skills │ │
│ └────┬──────┘ └────┬─────┘ └────┬─────┘ └─────┬───────┘ │
│ │ │ │ │ │
│ └──────────────┼─────────────┼───────────────┘ │
│ │ │ │
│ ┌───────────┴─────────────┴───────────┐ │
│ │ @sint/os-core (Orchestrator) │ │
│ │ Boot → Govern → React → Evidence │ │
│ └───────────┬─────────────────────────┘ │
│ │ │
│ ┌────────────────┼────────────────────┐ │
│ │ │ │ │
│ ┌──┴──────────┐ ┌──┴──────────┐ ┌─────┴──────────┐ │
│ │ OpenClaw │ │ SINT │ │ Evidence │ │
│ │ Adapter │ │ Protocol │ │ HUD │ │
│ │ (T0-T3) │ │ (Gateway) │ │ (Ledger View) │ │
│ └──┬──────────┘ └──┬──────────┘ └────────────────┘ │
│ │ │ │
│ │ ┌────────────┴─────────────────────┐ │
│ │ │ SINT Protocol Core │ │
│ │ │ • Capability Tokens (Ed25519) │ │
│ │ │ • Policy Gateway (32 endpoints) │ │
│ │ │ • Evidence Ledger (SHA-256) │ │
│ │ │ • 12 Protocol Bridges │ │
│ │ └───────────────────────────────────┘ │
│ │ │
│ ┌──┴──────────────────────────────────┐ │
│ │ OpenClaw Runtime │ │
│ │ • WebSocket Gateway (port 18789) │ │
│ │ • 20+ Channel Plugins │ │
│ │ • MCP Tool Router │ │
│ │ • Session Manager │ │
│ │ • Cron Scheduler │ │
│ │ • Docker Sandbox │ │
│ └──────────────────────────────────────┘ │
└──────────────────────────────────────────────────────────────┘
```
## Layer-by-layer
3D WebGL avatar with voice I/O, Conversation Compiler, 18 widget types. React Three Fiber.
31 feature modules, visual workflow builder, real-time agent orchestration.
LinkedIn automation, reply classification, CRM routing. Production agentic loops.
Video-to-content pipeline with 18 skills, multi-channel publishing.
Capability tokens, policy gateway, evidence ledger, 12 transport bridges.
Agent runtime: WebSocket gateway, channel plugins, MCP router, session manager, sandbox.
## The Protocol core
Every product and agent action flows through the same governance core. This is not an optional middleware — it's the only path to physical actuation.
Ed25519-signed tokens encode resource scope, allowed actions, physical constraints, time bounds, and a delegation chain of max 3 hops. Attenuation-only delegation: a child token's scope is always a subset of its parent's.
A single `intercept()` entry point. Every request validates schema, token, scope, rate limit, physical constraint, and tier assignment before reaching a transport bridge.
SHA-256 hash-chained append-only log. Every decision is recorded with a prevHash pointer, providing tamper evidence without requiring blockchain infrastructure.
Twelve bridges translate protocol-specific actions (MCP tools, ROS 2 topics, MAVLink commands, OPC UA writes, etc.) into a unified policy evaluation format.
## Cross-system policies
The Protocol's differentiating feature is **cross-system policies** — invariants that span multiple transport bridges simultaneously.
| Policy | Active when | Denies | Why |
| ------------------------ | -------------- | ------------------ | --------------------------------------------------------- |
| `no-fs-while-moving` | `robot.moving` | File writes, edits | Prevents controller corruption during motion |
| `no-exec-while-moving` | `robot.moving` | Shell execution | Prevents control-loop interference |
| `no-deploy-while-active` | `cmd_vel` | Deploys, restarts | Can't restart while velocity commands are active |
| `no-network-while-armed` | `drone.armed` | Network, exec | Safety-critical — no external access while drone is armed |
No single-protocol safety system can enforce these. The Protocol can because every bridge publishes state into the same gateway.
## Example: voice command to deploy
What happens when a user says "Jarvis, deploy the staging build":
Qwen3.5-Omni or OpenClaw Voice Wake transcribes input to text.
OpenClaw gateway routes to the active SINT agent session.
Agent decides: `exec("railway up --environment staging")`.
`@sint/openclaw-adapter` classifies the tool call as T2 (deploy action).
Is `robot.moving` active? No → continue. Is `drone.armed` active? No → continue.
Token scope check passes. Rate limit passes. Physical constraint not applicable. Decision: ALLOW.
SHA-256 entry written with prevHash linkage. TEE signature if configured.
The shell command runs. Output captured.
Agent output rewritten for natural speech: "Staging deploy is live."
Smile expression, head-nod animation, status widget ("Staging" → success, 3s).
New entry appears in real-time feed.
## Example: voice command to move a robot
"Jarvis, move the robot two meters forward":
Agent proposes `nodes.invoke("move_forward", distance=2)`.
T3 — physical, irreversible in the sense that a collision cannot be undone.
All clear.
T3 requires human approval. `approvalId = "apr-456"` is queued.
Surprised expression, thinking animation, action widget ("Approve 2m forward?", 30s timeout).
One click on the widget. Gateway resolves approval.
Robot moves 2m forward. StateTracker activates `robot.moving`.
File writes, shell execution, and deploys are automatically denied by cross-system policies.
`robot.moving` deactivates. Evidence ledger: full chain from request → approval → execution → completion.
## Where to read more
Detailed treatment of the Protocol layer.
How the products integrate through os-core.
T0–T3 and the Δ-factor escalation function.
All twelve transport bridges, per-resource state machines, profiles.