chat-sdk

name

chat-sdk

description

Build multi-platform chat bots with Chat SDK (`chat` npm package). Use when developers want to (1) Build a Slack, Teams, Google Chat, Discord, GitHub, or Linear bot, (2) Use the Chat SDK to handle mentions, messages, reactions, slash commands, cards, modals, or streaming, (3) Set up webhook handlers for chat platforms, (4) Send interactive cards or stream AI responses to chat platforms, (5) Build a custom adapter for a new chat platform. Triggers on "chat sdk", "chat bot", "slack bot", "teams bot", "discord bot", "@chat-adapter", "custom adapter", "build adapter", building bots that work across multiple chat platforms.

Chat SDK

Unified TypeScript SDK for building chat bots across Slack, Teams, Google Chat, Discord, GitHub, and Linear. Write bot logic once, deploy everywhere.

Critical: Read the bundled docs

The chat package ships with full documentation in node_modules/chat/docs/ and TypeScript source types. Always read these before writing code:

node_modules/chat/docs/           # Full documentation (MDX files)
node_modules/chat/dist/           # Built types (.d.ts files)

Key docs to read based on task:

• docs/getting-started.mdx — setup guides
• docs/usage.mdx — event handlers, threads, messages, channels
• docs/streaming.mdx — AI streaming with AI SDK
• docs/cards.mdx — JSX interactive cards
• docs/actions.mdx — button/dropdown handlers
• docs/modals.mdx — form dialogs (Slack only)
• docs/adapters.mdx — platform-specific adapter setup
• docs/state.mdx — state adapter config (Redis, ioredis, PostgreSQL, memory)

Also read the TypeScript types from node_modules/chat/dist/ to understand the full API surface.

Quick start

import { Chat } from "chat";
import { createSlackAdapter } from "@chat-adapter/slack";
import { createRedisState } from "@chat-adapter/state-redis";

const bot = new Chat({
  userName: "mybot",
  adapters: {
    slack: createSlackAdapter({
      botToken: process.env.SLACK_BOT_TOKEN!,
      signingSecret: process.env.SLACK_SIGNING_SECRET!,
    }),
  },
  state: createRedisState({ url: process.env.REDIS_URL! }),
});

bot.onNewMention(async (thread) => {
  await thread.subscribe();
  await thread.post("Hello! I'm listening to this thread.");
});

bot.onSubscribedMessage(async (thread, message) => {
  await thread.post(`You said: ${message.text}`);
});

Core concepts

• Chat — main entry point, coordinates adapters and routes events
• Adapters — platform-specific (Slack, Teams, GChat, Discord, GitHub, Linear)
• State — pluggable persistence (Redis or PostgreSQL for prod, memory for dev)
• Thread — conversation thread with post(), subscribe(), startTyping()
• Message — normalized format with text, formatted (mdast AST), raw
• Channel — container for threads, supports listing and posting

Event handlers

Handler	Trigger
onNewMention	Bot @-mentioned in unsubscribed thread
onSubscribedMessage	Any message in subscribed thread
onNewMessage(regex)	Messages matching pattern in unsubscribed threads
onSlashCommand("/cmd")	Slash command invocations
onReaction(emojis)	Emoji reactions added/removed
onAction(actionId)	Button clicks and dropdown selections
onAssistantThreadStarted	Slack Assistants API thread opened
onAppHomeOpened	Slack App Home tab opened

Streaming

Pass any AsyncIterable<string> to thread.post(). Works with AI SDK's textStream:

import { ToolLoopAgent } from "ai";
const agent = new ToolLoopAgent({ model: "anthropic/claude-4.5-sonnet" });

bot.onNewMention(async (thread, message) => {
  const result = await agent.stream({ prompt: message.text });
  await thread.post(result.textStream);
});

Cards (JSX)

Set jsxImportSource: "chat" in tsconfig. Components: Card, CardText, Button, Actions, Fields, Field, Select, SelectOption, Image, Divider, LinkButton, Section, RadioSelect.

await thread.post(
  <Card title="Order #1234">
    <CardText>Your order has been received!</CardText>
    <Actions>
      <Button id="approve" style="primary">Approve</Button>
      <Button id="reject" style="danger">Reject</Button>
    </Actions>
  </Card>
);

Packages

Package	Purpose
chat	Core SDK
@chat-adapter/slack	Slack
@chat-adapter/teams	Microsoft Teams
@chat-adapter/gchat	Google Chat
@chat-adapter/discord	Discord
@chat-adapter/github	GitHub Issues
@chat-adapter/linear	Linear Issues
@chat-adapter/state-redis	Redis state (production)
@chat-adapter/state-ioredis	ioredis state (alternative)
@chat-adapter/state-pg	PostgreSQL state (production)
@chat-adapter/state-memory	In-memory state (development)

Changesets (Release Flow)

This monorepo uses Changesets for versioning and changelogs. Every PR that changes a package's behavior must include a changeset.

pnpm changeset
# → select affected package(s) (e.g. @chat-adapter/slack, chat)
# → choose bump type: patch (fixes), minor (features), major (breaking)
# → write a short summary for the CHANGELOG

This creates a file in .changeset/ — commit it with the PR. When merged to main, the Changesets GitHub Action opens a "Version Packages" PR to bump versions and update CHANGELOGs. Merging that PR publishes to npm.

Building a custom adapter

To create a community or vendor adapter, implement the Adapter interface from chat and read:

• docs/contributing/building.mdx — full step-by-step guide (uses a Matrix adapter as example)
• docs/contributing/testing.mdx — testing your adapter
• docs/contributing/publishing.mdx — npm naming conventions and publishing

The adapter must implement handleWebhook, parseMessage, postMessage, editMessage, deleteMessage, thread ID encoding/decoding, and a FormatConverter (extend BaseFormatConverter from chat). Use @chat-adapter/shared for error classes and message utilities.

Webhook setup

Each adapter exposes a webhook handler via bot.webhooks.{platform}. Wire these to your HTTP framework's routes (e.g. Next.js API routes, Hono, Express).