elizaOS Core (Python)

The Python implementation of elizaOS Core - the runtime and types for elizaOS AI agents.

Installation

From Repository (Development)

# From the repo root
cd eliza

# Create and activate virtual environment
python -m venv venv
source venv/bin/activate  # On Windows: venv\Scripts\activate

# Install the core package
pip install -e packages/python

# Install an LLM provider (required)
pip install -e plugins/plugin-openai/python

# Install a database adapter (required for message handling)
pip install -e plugins/plugin-inmemorydb/python

From PyPI

pip install elizaos elizaos-plugin-openai elizaos-plugin-inmemorydb

Quick Start

Run the Chat Example

# Set your OpenAI API key
export OPENAI_API_KEY="your-key"

# Run the example
python examples/chat/python/chat.py

Create Your Own Agent

from __future__ import annotations
import asyncio
import os
from pathlib import Path

from dotenv import load_dotenv
load_dotenv()  # Load .env file

from uuid6 import uuid7
from elizaos import Character, ChannelType, Content, Memory
from elizaos.runtime import AgentRuntime
from elizaos_plugin_openai import get_openai_plugin
from elizaos_plugin_inmemorydb import plugin as inmemorydb_plugin

async def main() -> None:
    # Define your agent's character
    character = Character(
        name="Eliza",
        username="eliza",
        bio="A helpful AI assistant.",
        system="You are helpful and concise.",
    )

    # Create runtime with plugins
    runtime = AgentRuntime(
        character=character,
        plugins=[
            get_openai_plugin(),    # LLM provider
            inmemorydb_plugin,      # Database adapter
        ],
    )

    user_id = uuid7()
    room_id = uuid7()

    try:
        await runtime.initialize()
        print(f"🤖 Chat with {character.name} (type 'quit' to exit)\n")

        while True:
            user_input = input("You: ")
            if not user_input.strip() or user_input.lower() in ("quit", "exit"):
                break

            message = Memory(
                entity_id=user_id,
                room_id=room_id,
                content=Content(
                    text=user_input,
                    source="cli",
                    channel_type=ChannelType.DM.value,
                ),
            )

            result = await runtime.message_service.handle_message(runtime, message)
            print(f"\n{character.name}: {result.response_content.text}\n")

        print("Goodbye! 👋")
    finally:
        await runtime.stop()

if __name__ == "__main__":
    asyncio.run(main())

Features

• Strong typing with Pydantic models and full type hints
• Plugin architecture for extensibility
• Character configuration for defining agent personalities
• Memory system for conversation history and knowledge
• Event system for reactive programming
• Service abstraction for external integrations

Runtime Settings (cross-language parity)

These settings are read by the runtime/message loop to keep behavior aligned with the TypeScript and Rust implementations:

• ALLOW_NO_DATABASE: when truthy, the runtime may run without a database adapter (benchmarks/tests).
• USE_MULTI_STEP: when truthy, enable the iterative multi-step workflow.
• MAX_MULTISTEP_ITERATIONS: maximum iterations for multi-step mode (default: 6).

Benchmark & Trajectory Tracing

Benchmarks and harnesses can attach metadata to inbound messages:

• message.metadata.trajectoryStepId: enables trajectory tracing for provider access + model calls.
• message.metadata.benchmarkContext: enables the CONTEXT_BENCH provider and sets state.values["benchmark_has_context"]=True, which forces action-based execution to exercise the full loop.

Model output contract (XML preferred, plain text tolerated)

The canonical message loop expects model outputs in the <response>...</response> XML format (with <actions>, <providers>, and <text> fields).

Some deterministic/offline backends may return plain text instead. In that case, the runtime will treat the raw output as a simple REPLY so the system remains usable even when strict XML formatting is unavailable.

Core Types

• UUID - Universally unique identifier
• Content - Message content with text, actions, attachments
• Memory - Stored message or information
• Entity - User or agent representation
• Room - Conversation context
• World - Collection of rooms and entities

Components

• Action - Define agent capabilities
• Provider - Supply contextual information
• Evaluator - Post-interaction analysis
• Service - Long-running integrations

Plugin System

from elizaos import Plugin, Action, Provider

my_plugin = Plugin(
    name="my-plugin",
    description="A custom plugin",
    actions=[...],
    providers=[...],
)

Available Plugins

LLM Providers

Database Adapters

Platform Integrations

Environment Variables

# Required for OpenAI plugin
OPENAI_API_KEY=sk-...

# Optional
LOG_LEVEL=INFO

Development

# Install development dependencies
pip install -e ".[dev]"

# (Reproducible/pinned) Generate lockfiles used by CI
pip install pip-tools
pip-compile requirements.in -o requirements.lock
pip-compile requirements-dev.in -o requirements-dev.lock

# Run tests
pytest

# Type checking
mypy elizaos

# Linting
ruff check elizaos

Examples

See examples/ directory for complete working examples:

• examples/chat/python/ - CLI chat agent
• examples/telegram/python/ - Telegram bot
• examples/discord/python/ - Discord bot
• examples/rest-api/fastapi/ - REST API server

License

MIT