npm install @qwen-code/channel-base

import { ChannelBase } from '@qwen-code/channel-base';
import type {
  ChannelConfig,
  Envelope,
  AcpBridge,
} from '@qwen-code/channel-base';

class MyChannel extends ChannelBase {
  async connect(): Promise<void> {
    // Connect to platform API, register message handlers.
    // When a message arrives, build an Envelope and call:
    //   this.handleInbound(envelope)
  }

  async sendMessage(chatId: string, text: string): Promise<void> {
    // Deliver the agent's response to the platform.
  }

  disconnect(): void {
    // Clean up connections on shutdown.
  }
}

import type { ChannelPlugin } from '@qwen-code/channel-base';

export const plugin: ChannelPlugin = {
  channelType: 'my-platform',
  displayName: 'My Platform',
  requiredConfigFields: ['apiKey'],
  createChannel: (name, config, bridge, options) =>
    new MyChannel(name, config, bridge, options),
};

Inbound:  Platform message
            → Envelope (with attachments)
            → GroupGate (group policy + mention gating)
            → SenderGate (allowlist / pairing / open)
            → Slash commands (/clear, /help, /status)
            → SessionRouter (resolve or create ACP session)
            → Resolve attachments (images → bridge, files → prompt text)
            → AcpBridge.prompt() → agent

Outbound: Agent response
            → BlockStreamer (if enabled: split into blocks at paragraph boundaries)
            → sendMessage() → platform

constructor(name: string, config: ChannelConfig, bridge: AcpBridge, options?: ChannelBaseOptions)

constructor(options: { cliEntryPath: string; cwd: string; model?: string })

constructor(bridge: AcpBridge, defaultCwd: string, scope?: SessionScope, persistPath?: string)

constructor(policy: SenderPolicy, allowedUsers?: string[], pairingStore?: PairingStore)

constructor(policy?: GroupPolicy, groups?: Record<string, GroupConfig>)

constructor(channelName: string)

interface Envelope {
  channelName: string; // your channel instance name
  senderId: string; // stable, unique sender ID
  senderName: string; // display name
  chatId: string; // distinguishes DMs from groups
  text: string; // message text (@mentions stripped)
  messageId?: string; // platform message ID
  threadId?: string; // for thread-scoped sessions
  isGroup: boolean; // true for group chats
  isMentioned: boolean; // true if bot was @mentioned
  isReplyToBot: boolean; // true if replying to bot's message
  referencedText?: string; // quoted message text
  imageBase64?: string; // base64-encoded image (legacy — prefer attachments)
  imageMimeType?: string; // e.g. 'image/jpeg' (legacy — prefer attachments)
  attachments?: Attachment[]; // structured file/image/audio/video attachments
}

interface Attachment {
  type: 'image' | 'file' | 'audio' | 'video';
  data?: string; // base64-encoded data (images, small files)
  filePath?: string; // absolute path to local file (large files)
  mimeType: string; // e.g. 'application/pdf', 'image/jpeg'
  fileName?: string; // original file name from the platform
}