clanker-agent/packages/web-ui

@mariozechner/pi-web-ui

Reusable web UI components for building AI chat interfaces powered by @mariozechner/pi-ai and @mariozechner/pi-agent-core.

Built with mini-lit web components and Tailwind CSS v4.

Features

• Chat UI: Complete interface with message history, streaming, and tool execution
• Tools: JavaScript REPL, document extraction, and artifacts (HTML, SVG, Markdown, etc.)
• Attachments: PDF, DOCX, XLSX, PPTX, images with preview and text extraction
• Artifacts: Interactive HTML, SVG, Markdown with sandboxed execution
• Storage: IndexedDB-backed storage for sessions, API keys, and settings
• CORS Proxy: Automatic proxy handling for browser environments
• Custom Providers: Support for Ollama, LM Studio, vLLM, and OpenAI-compatible APIs

Installation

npm install @mariozechner/pi-web-ui @mariozechner/pi-agent-core @mariozechner/pi-ai

Quick Start

See the example directory for a complete working application.

import { Agent } from "@mariozechner/pi-agent-core";
import { getModel } from "@mariozechner/pi-ai";
import {
  ChatPanel,
  AppStorage,
  IndexedDBStorageBackend,
  ProviderKeysStore,
  SessionsStore,
  SettingsStore,
  setAppStorage,
  defaultConvertToLlm,
  ApiKeyPromptDialog,
} from "@mariozechner/pi-web-ui";
import "@mariozechner/pi-web-ui/app.css";

// Set up storage
const settings = new SettingsStore();
const providerKeys = new ProviderKeysStore();
const sessions = new SessionsStore();

const backend = new IndexedDBStorageBackend({
  dbName: "my-app",
  version: 1,
  stores: [
    settings.getConfig(),
    providerKeys.getConfig(),
    sessions.getConfig(),
    SessionsStore.getMetadataConfig(),
  ],
});

settings.setBackend(backend);
providerKeys.setBackend(backend);
sessions.setBackend(backend);

const storage = new AppStorage(
  settings,
  providerKeys,
  sessions,
  undefined,
  backend,
);
setAppStorage(storage);

// Create agent
const agent = new Agent({
  initialState: {
    systemPrompt: "You are a helpful assistant.",
    model: getModel("anthropic", "claude-sonnet-4-5-20250929"),
    thinkingLevel: "off",
    messages: [],
    tools: [],
  },
  convertToLlm: defaultConvertToLlm,
});

// Create chat panel
const chatPanel = new ChatPanel();
await chatPanel.setAgent(agent, {
  onApiKeyRequired: (provider) => ApiKeyPromptDialog.prompt(provider),
});

document.body.appendChild(chatPanel);

Architecture

┌─────────────────────────────────────────────────────┐
│                    ChatPanel                         │
│  ┌─────────────────────┐  ┌─────────────────────┐   │
│  │   AgentInterface    │  │   ArtifactsPanel    │   │
│  │  (messages, input)  │  │  (HTML, SVG, MD)    │   │
│  └─────────────────────┘  └─────────────────────┘   │
└─────────────────────────────────────────────────────┘
                          │
                          ▼
┌─────────────────────────────────────────────────────┐
│              Agent (from pi-agent-core)              │
│  - State management (messages, model, tools)         │
│  - Event emission (agent_start, message_update, ...) │
│  - Tool execution                                    │
└─────────────────────────────────────────────────────┘
                          │
                          ▼
┌─────────────────────────────────────────────────────┐
│                   AppStorage                         │
│  ┌──────────┐ ┌──────────┐ ┌──────────┐            │
│  │ Settings │ │ Provider │ │ Sessions │            │
│  │  Store   │ │Keys Store│ │  Store   │            │
│  └──────────┘ └──────────┘ └──────────┘            │
│                     │                               │
│              IndexedDBStorageBackend                │
└─────────────────────────────────────────────────────┘

Components

ChatPanel

High-level chat interface with built-in artifacts panel.

const chatPanel = new ChatPanel();
await chatPanel.setAgent(agent, {
  // Prompt for API key when needed
  onApiKeyRequired: async (provider) => ApiKeyPromptDialog.prompt(provider),

  // Hook before sending messages
  onBeforeSend: async () => {
    /* save draft, etc. */
  },

  // Handle cost display click
  onCostClick: () => {
    /* show cost breakdown */
  },

  // Custom sandbox URL for browser extensions
  sandboxUrlProvider: () => chrome.runtime.getURL("sandbox.html"),

  // Add custom tools
  toolsFactory: (
    agent,
    agentInterface,
    artifactsPanel,
    runtimeProvidersFactory,
  ) => {
    const replTool = createJavaScriptReplTool();
    replTool.runtimeProvidersFactory = runtimeProvidersFactory;
    return [replTool];
  },
});

AgentInterface

Lower-level chat interface for custom layouts.

const chat = document.createElement("agent-interface") as AgentInterface;
chat.session = agent;
chat.enableAttachments = true;
chat.enableModelSelector = true;
chat.enableThinkingSelector = true;
chat.onApiKeyRequired = async (provider) => {
  /* ... */
};
chat.onBeforeSend = async () => {
  /* ... */
};

Properties:

• session: Agent instance
• enableAttachments: Show attachment button (default: true)
• enableModelSelector: Show model selector (default: true)
• enableThinkingSelector: Show thinking level selector (default: true)
• showThemeToggle: Show theme toggle (default: false)

Agent (from pi-agent-core)

import { Agent } from '@mariozechner/pi-agent-core';

const agent = new Agent({
  initialState: {
    model: getModel('anthropic', 'claude-sonnet-4-5-20250929'),
    systemPrompt: 'You are helpful.',
    thinkingLevel: 'off',
    messages: [],
    tools: [],
  },
  convertToLlm: defaultConvertToLlm,
});

// Events
agent.subscribe((event) => {
  switch (event.type) {
    case 'agent_start': // Agent loop started
    case 'agent_end':   // Agent loop finished
    case 'turn_start':  // LLM call started
    case 'turn_end':    // LLM call finished
    case 'message_start':
    case 'message_update': // Streaming update
    case 'message_end':
      break;
  }
});

// Send message
await agent.prompt('Hello!');
await agent.prompt({ role: 'user-with-attachments', content: 'Check this', attachments, timestamp: Date.now() });

// Control
agent.abort();
agent.setModel(newModel);
agent.setThinkingLevel('medium');
agent.setTools([...]);
agent.queueMessage(customMessage);

Message Types

UserMessageWithAttachments

User message with file attachments:

const message: UserMessageWithAttachments = {
  role: "user-with-attachments",
  content: "Analyze this document",
  attachments: [pdfAttachment],
  timestamp: Date.now(),
};

// Type guard
if (isUserMessageWithAttachments(msg)) {
  console.log(msg.attachments);
}

ArtifactMessage

For session persistence of artifacts:

const artifact: ArtifactMessage = {
  role: "artifact",
  action: "create", // or 'update', 'delete'
  filename: "chart.html",
  content: "<div>...</div>",
  timestamp: new Date().toISOString(),
};

// Type guard
if (isArtifactMessage(msg)) {
  console.log(msg.filename);
}

Custom Message Types

Extend via declaration merging:

interface SystemNotification {
  role: "system-notification";
  message: string;
  level: "info" | "warning" | "error";
  timestamp: string;
}

declare module "@mariozechner/pi-agent-core" {
  interface CustomAgentMessages {
    "system-notification": SystemNotification;
  }
}

// Register renderer
registerMessageRenderer("system-notification", {
  render: (msg) => html`<div class="alert">${msg.message}</div>`,
});

// Extend convertToLlm
function myConvertToLlm(messages: AgentMessage[]): Message[] {
  const processed = messages.map((m) => {
    if (m.role === "system-notification") {
      return {
        role: "user",
        content: `<system>${m.message}</system>`,
        timestamp: Date.now(),
      };
    }
    return m;
  });
  return defaultConvertToLlm(processed);
}

Message Transformer

convertToLlm transforms app messages to LLM-compatible format:

import {
  defaultConvertToLlm,
  convertAttachments,
} from "@mariozechner/pi-web-ui";

// defaultConvertToLlm handles:
// - UserMessageWithAttachments → user message with image/text content blocks
// - ArtifactMessage → filtered out (UI-only)
// - Standard messages (user, assistant, toolResult) → passed through

Tools

JavaScript REPL

Execute JavaScript in a sandboxed browser environment:

import { createJavaScriptReplTool } from "@mariozechner/pi-web-ui";

const replTool = createJavaScriptReplTool();

// Configure runtime providers for artifact/attachment access
replTool.runtimeProvidersFactory = () => [
  new AttachmentsRuntimeProvider(attachments),
  new ArtifactsRuntimeProvider(artifactsPanel, agent, true), // read-write
];

agent.setTools([replTool]);

Extract Document

Extract text from documents at URLs:

import { createExtractDocumentTool } from "@mariozechner/pi-web-ui";

const extractTool = createExtractDocumentTool();
extractTool.corsProxyUrl = "https://corsproxy.io/?";

agent.setTools([extractTool]);

Artifacts Tool

Built into ArtifactsPanel, supports: HTML, SVG, Markdown, text, JSON, images, PDF, DOCX, XLSX.

const artifactsPanel = new ArtifactsPanel();
artifactsPanel.agent = agent;

// The tool is available as artifactsPanel.tool
agent.setTools([artifactsPanel.tool]);

Custom Tool Renderers

import {
  registerToolRenderer,
  type ToolRenderer,
} from "@mariozechner/pi-web-ui";

const myRenderer: ToolRenderer = {
  render(params, result, isStreaming) {
    return {
      content: html`<div>...</div>`,
      isCustom: false, // true = no card wrapper
    };
  },
};

registerToolRenderer("my_tool", myRenderer);

Storage

Setup

import {
  AppStorage,
  IndexedDBStorageBackend,
  SettingsStore,
  ProviderKeysStore,
  SessionsStore,
  CustomProvidersStore,
  setAppStorage,
  getAppStorage,
} from "@mariozechner/pi-web-ui";

// Create stores
const settings = new SettingsStore();
const providerKeys = new ProviderKeysStore();
const sessions = new SessionsStore();
const customProviders = new CustomProvidersStore();

// Create backend with all store configs
const backend = new IndexedDBStorageBackend({
  dbName: "my-app",
  version: 1,
  stores: [
    settings.getConfig(),
    providerKeys.getConfig(),
    sessions.getConfig(),
    SessionsStore.getMetadataConfig(),
    customProviders.getConfig(),
  ],
});

// Wire stores to backend
settings.setBackend(backend);
providerKeys.setBackend(backend);
sessions.setBackend(backend);
customProviders.setBackend(backend);

// Create and set global storage
const storage = new AppStorage(
  settings,
  providerKeys,
  sessions,
  customProviders,
  backend,
);
setAppStorage(storage);

SettingsStore

Key-value settings:

await storage.settings.set("proxy.enabled", true);
await storage.settings.set("proxy.url", "https://proxy.example.com");
const enabled = await storage.settings.get<boolean>("proxy.enabled");

ProviderKeysStore

API keys by provider:

await storage.providerKeys.set("anthropic", "sk-ant-...");
const key = await storage.providerKeys.get("anthropic");
const providers = await storage.providerKeys.list();

SessionsStore

Chat sessions with metadata:

// Save session
await storage.sessions.save(sessionData, metadata);

// Load session
const data = await storage.sessions.get(sessionId);
const metadata = await storage.sessions.getMetadata(sessionId);

// List sessions (sorted by lastModified)
const allMetadata = await storage.sessions.getAllMetadata();

// Update title
await storage.sessions.updateTitle(sessionId, "New Title");

// Delete
await storage.sessions.delete(sessionId);

CustomProvidersStore

Custom LLM providers:

const provider: CustomProvider = {
  id: crypto.randomUUID(),
  name: "My Ollama",
  type: "ollama",
  baseUrl: "http://localhost:11434",
};

await storage.customProviders.set(provider);
const all = await storage.customProviders.getAll();

Attachments

Load and process files:

import { loadAttachment, type Attachment } from "@mariozechner/pi-web-ui";

// From File input
const file = inputElement.files[0];
const attachment = await loadAttachment(file);

// From URL
const attachment = await loadAttachment("https://example.com/doc.pdf");

// From ArrayBuffer
const attachment = await loadAttachment(arrayBuffer, "document.pdf");

// Attachment structure
interface Attachment {
  id: string;
  type: "image" | "document";
  fileName: string;
  mimeType: string;
  size: number;
  content: string; // base64 encoded
  extractedText?: string; // For documents
  preview?: string; // base64 preview image
}

Supported formats: PDF, DOCX, XLSX, PPTX, images, text files.

CORS Proxy

For browser environments with CORS restrictions:

import {
  createStreamFn,
  shouldUseProxyForProvider,
  isCorsError,
} from "@mariozechner/pi-web-ui";

// AgentInterface auto-configures proxy from settings
// For manual setup:
agent.streamFn = createStreamFn(async () => {
  const enabled = await storage.settings.get<boolean>("proxy.enabled");
  return enabled ? await storage.settings.get<string>("proxy.url") : undefined;
});

// Providers requiring proxy:
// - zai: always
// - anthropic: only OAuth tokens (sk-ant-oat-*)

Dialogs

SettingsDialog

import {
  SettingsDialog,
  ProvidersModelsTab,
  ProxyTab,
  ApiKeysTab,
} from "@mariozechner/pi-web-ui";

SettingsDialog.open([
  new ProvidersModelsTab(), // Custom providers + model list
  new ProxyTab(), // CORS proxy settings
  new ApiKeysTab(), // API keys per provider
]);

SessionListDialog

import { SessionListDialog } from "@mariozechner/pi-web-ui";

SessionListDialog.open(
  async (sessionId) => {
    /* load session */
  },
  (deletedId) => {
    /* handle deletion */
  },
);

ApiKeyPromptDialog

import { ApiKeyPromptDialog } from "@mariozechner/pi-web-ui";

const success = await ApiKeyPromptDialog.prompt("anthropic");

ModelSelector

import { ModelSelector } from "@mariozechner/pi-web-ui";

ModelSelector.open(currentModel, (selectedModel) => {
  agent.setModel(selectedModel);
});

Styling

Import the pre-built CSS:

import "@mariozechner/pi-web-ui/app.css";

Or use Tailwind with custom config:

@import "@mariozechner/mini-lit/themes/claude.css";
@tailwind base;
@tailwind components;
@tailwind utilities;

Internationalization

import { i18n, setLanguage, translations } from "@mariozechner/pi-web-ui";

// Add translations
translations.de = {
  "Loading...": "Laden...",
  "No sessions yet": "Noch keine Sitzungen",
};

setLanguage("de");
console.log(i18n("Loading...")); // "Laden..."

Examples

• example/ - Complete web app with sessions, artifacts, custom messages
• sitegeist - Browser extension using pi-web-ui

Known Issues

• PersistentStorageDialog: Currently broken

License

MIT