exo-core - Exo Docs

The exo-core package is the foundation of the Exo framework. It provides all the building blocks for creating and running LLM-powered agents: the type system, configuration, tool abstractions, the agent class, execution runners, multi-agent swarms, lifecycle hooks, events, and more.

Installation

Part of the exo-ai monorepo:

bash

git clone https://github.com/Midsphere-AI/exo-ai.git && cd exo-ai
uv sync

Import Patterns

The top-level exo namespace re-exports the most commonly used classes:

python

from exo import Agent, Tool, FunctionTool, tool, run, Swarm
from exo import ParallelGroup, SerialGroup, SwarmNode

For more specific imports, use the individual modules:

python

from exo.types import UserMessage, AssistantMessage, RunResult, StreamEvent
from exo.config import ModelConfig, AgentConfig, RunConfig, parse_model_string
from exo.registry import Registry, RegistryError, agent_registry, tool_registry
from exo.events import EventBus, EventHandler
from exo.hooks import HookPoint, HookManager, Hook, run_hooks
from exo.tool import Tool, FunctionTool, tool, ToolError
from exo.agent import Agent, AgentError
from exo.runner import run
from exo.swarm import Swarm, SwarmError
from exo.human import HumanInputTool, HumanInputHandler, ConsoleHandler
from exo.loader import load_agents, load_swarm, register_agent_class, LoaderError
from exo.skills import Skill, SkillRegistry, ConflictStrategy, SkillError

Namespace Package Architecture

exo-core uses pkgutil.extend_path() to create a namespace package. This allows other Exo packages (such as exo-models, exo-context) to add modules to the exo namespace without conflicts.

Modules

Module	Description
types	Core message types, agent I/O, run results, streaming events
config	Configuration dataclasses for models, agents, tasks, and runs
registry	Generic named registry with duplicate detection
events	Async event bus for decoupled communication
hooks	Lifecycle hook system for agent execution interception
tool	Tool ABC, FunctionTool wrapper, @tool decorator
agent	The Agent class — the core autonomous unit
runner	`run()`, `run.sync()`, `run.stream()` execution API
swarm	Multi-agent orchestration with workflow, handoff, and team modes
human	Human-in-the-loop tool and input handlers
loader	YAML-based agent and swarm loading
skills	Multi-source skill registry

Quick Example

python

import asyncio
from exo import Agent, tool, run

@tool
def get_weather(city: str) -> str:
    """Get the current weather for a city."""
    return f"It is sunny in {city}."

agent = Agent(
    name="weather_bot",
    model="openai:gpt-4o",
    instructions="You are a helpful weather assistant.",
    tools=[get_weather],
)

result = run.sync(agent, "What is the weather in Tokyo?")
print(result.output)