Browser SDK

The browser-optimized SDK for connecting web applications to the iii engine.

Documentation

Full API reference: https://iii.dev/docs/api-reference/sdk-browser

Install

npm install iii-browser-sdk

Key Exports

Key Differences from Node SDK

• No custom WebSocket headers — uses query parameters for auth tokens
• No Logger export — use browser console or your own logging
• No worker metadata telemetry reporting
• Connects directly via ws:// or wss:// URL (no registerWorker URL options)
• Same function/trigger/channel API surface as the Node SDK

Quick Start

import { registerWorker, TriggerAction } from 'iii-browser-sdk'

const iii = registerWorker('ws://localhost:49135')

iii.registerFunction('ui::greet', async (data) => {
  return { message: `Hello, ${data.name}!` }
})

const result = await iii.trigger({
  function_id: 'backend::get-user',
  payload: { userId: '123' },
})

await iii.trigger({
  function_id: 'analytics::track',
  payload: { event: 'page_view' },
  action: TriggerAction.Void(),
})

Common Patterns

Code using this pattern commonly includes, when relevant:

• registerWorker('ws://host:49135') — connect from browser
• registerWorker('wss://host:49135') — connect with TLS in production
• iii.registerFunction(id, handler) — register browser-side handler
• iii.trigger({ function_id, payload }) — call server-side functions
• iii.trigger({ ..., action: TriggerAction.Void() }) — fire-and-forget from browser
• Stream connections at ws://host:3112/stream/{name}/{group} for real-time updates

Pattern Boundaries

• For server-side Node.js workers, prefer iii-node-sdk.
• For real-time stream consumption patterns, see iii-realtime-streams.
• For Python or Rust workers, see iii-python-sdk or iii-rust-sdk.
• Stay with iii-browser-sdk when the client is a web browser.

When to Use

• Use this skill when the task is primarily about iii-browser-sdk in the iii engine.
• Triggers when the request directly asks for this pattern or an equivalent implementation.

Boundaries

• Never use this skill as a generic fallback for unrelated tasks.
• You must not apply this skill when a more specific iii skill is a better fit.
• Always verify environment and safety constraints before applying examples from this skill.