First Steps: Choose Your Interface

First Steps: Choose Your Interface#

Pantheon provides three ways to interact with AI agents. Choose the one that fits your needs.

REPL (Command Line)#

Best for: Quick experiments, developers, command-line lovers

The REPL is the fastest way to start using Pantheon. It provides a rich command-line interface with syntax highlighting, file viewing, and more.

# Start with default settings
pantheon cli

# Or specify a team template
pantheon cli --template data_research_team

Features:

  • Syntax highlighting for code

  • /view <file> - Full-screen file viewer

  • /compress - Compress long conversations

  • Auto-completion and history

➡️ Learn more: REPL Interface

Web UI (ChatRoom)#

Best for: Demos, non-technical users, visual workflow

The ChatRoom provides a web-based interface accessible from any browser.

# Start the multi-agent chatroom
pantheon ui --auto-start-nats --auto-ui

Features:

  • Clean visual interface

  • File upload support

  • Session management

  • Multi-user support

➡️ Learn more: Web UI (ChatRoom)

Python API#

Best for: Developers, integrations, custom applications

Full programmatic control over agents and teams.

import asyncio
from pantheon.agent import Agent

async def main():
    agent = Agent(
        name="assistant",
        instructions="You are a helpful assistant."
    )

    # Single query
    response = await agent.run("Hello!")
    print(response.content)

    # Or interactive chat
    await agent.chat()

asyncio.run(main())

Features:

  • Full control over agent behavior

  • Easy integration with existing code

  • Async/await support

  • Custom toolsets

➡️ Learn more: Python API

Shared Configuration#

All three interfaces share the same configuration system through the .pantheon/ directory:

.pantheon/
├── settings.json    # Global settings (models, API keys, etc.)
├── mcp.json         # MCP server configuration
├── agents/          # Agent templates (markdown files)
├── teams/           # Team templates
└── prompts/         # Reusable prompt snippets

This means:

  • Configure once, use everywhere

  • Same agent templates work in REPL, UI, and API

  • Switch between interfaces freely

➡️ Learn more: Configuration

Quick Comparison#

Feature

REPL

Web UI

Python API

Setup time

Instant

1 minute

5 minutes

Best for

Power users

Everyone

Developers

Customization

Medium

Low

Full

Learning curve

Easy

Very easy

Medium

Next Steps#

Ready to build your first agent? Continue to 5-Minute Tutorial.