pnpm add @gao/system-sdk

import { GaoSDK } from '@gao/system-sdk'

const sdk = new GaoSDK({
  domain: 'myapp.gao',
  apiKey: process.env.GAO_API_KEY,
})

await sdk.transport.message.send({
  to:         'alice.gao',         // recipient's Gao Domain
  content:    'Hello!',
  type?:      'text',              // 'text' | 'notification' | 'agent_action'
  encrypted?: true,                // default true — always E2EE
})

const unsub = sdk.transport.message.subscribe((msg) => {
  console.log(msg.from)                // "alice.gao"
  console.log(msg.decrypted.content)  // decrypted message text
  console.log(msg.decrypted.type)     // message type
  console.log(msg.timestamp)          // unix ms
})

// Stop listening
unsub()

// Agent sends with its own identity (not the domain owner's)
await sdk.transport.message.sendAsAgent(
  'booking-bot-id',       // registered agent ID
  'customer-routing-tag', // recipient
  'Your booking is confirmed for tomorrow at 3pm.'
)

// Select best relay node for a recipient
const route = await sdk.transport.selectRoute({
  recipient: 'alice.gao',
  priority: 'low_latency',    // 'low_latency' | 'high_reliability'
})
// route.node_endpoint, route.latency_ms, route.region

// Validate a relay path
const valid = await sdk.transport.validateRelayPath([
  'relay1.meshii.app',
  'relay2.meshii.app',
])

// Default: no storage (messages lost on app close)
sdk.transport.setStorageMode('none')

// Save on device (encrypted)
sdk.transport.setStorageMode('local')

// Backup to GaoStorage (user pays fee)
sdk.transport.setStorageMode('depin')

import { useMessages } from '@gao/system-sdk/react'

function ChatWindow({ contact }: { contact: string }) {
  const { messages, send, loading } = useMessages(sdk, contact)

  return (
    <div>
      {messages.map(msg => (
        <div key={msg.id} className={msg.from === sdk.domain ? 'sent' : 'received'}>
          {msg.decrypted.content}
        </div>
      ))}
      <input
        onKeyDown={(e) => {
          if (e.key === 'Enter') send(e.currentTarget.value)
        }}
      />
    </div>
  )
}

pnpm add @gao/meshii-sdk

import { MeshiiClient } from '@gao/meshii-sdk'

const client = new MeshiiClient({
  network: 'gao-depin',
  apiKey: 'your_api_key',
})

await client.init({ identity: passkeyOrGaoDomain })

await client.send({ to: 'alice.gao', content: 'Hello!' })

client.onMessage((msg) => {
  console.log(msg.decrypted.content)
})

await sdk.transport.message.send({
  to: customerDomain,
  content: `Confirmed: ${service} on ${date} at ${time}. Reply to reschedule.`,
  type: 'notification',
})

await sdk.transport.message.send({
  to: merchantDomain,
  content: JSON.stringify({
    type: 'payment_received',
    amount: '25.00',
    currency: 'USDC',
    from: customerDomain,
  }),
  type: 'agent_action',
})

const unsub = sdk.transport.message.subscribe(async (msg) => {
  if (msg.decrypted.type === 'text') {
    // Run agent to generate reply
    const reply = await runSupportAgent(msg.decrypted.content)
    await sdk.transport.message.sendAsAgent('support-bot', msg.from, reply)
  }
})

// Run at 9am daily — sends reminders via Meshii
const job = await sdk.intelligence.scheduler.create({
  agent_id: 'reminder-agent',
  owner_domain: 'myapp.gao',
  trigger_type: 'cron',
  trigger_config: { expression: '0 9 * * *', timezone: 'America/Chicago' },
})
// Agent sends via sdk.transport automatically during execution

POST /transport/messages
Auth: Bearer token
Body: { to: string, content: string, type?: string, encrypted?: boolean }
Response: { message_id: string, delivered: boolean }

WebSocket: wss://relay.meshii.app/collab?token=<jwt>
Events (server → client):
  { type: "message", from: string, content: string, timestamp: number }
  { type: "ack", message_id: string }
  { type: "ping" }

const cap = await sdk.developer.capability.request('transport:message:send', 'myapp.gao', 3600)
// SDK attaches automatically to sdk.transport calls

const sdk = new GaoSDK({
  domain: 'myapp.gao',
  apiKey: process.env.GAO_API_KEY,
  environment: 'testnet',   // ← use testnet
})