---
layout: default
title: "(Advanced) Multi-Agents"
parent: "Design Pattern"
nav_order: 7
---

# (Advanced) Multi-Agents

Multiple [Agents](./flow.md) can work together by handling subtasks and communicating the progress. 
Communication between agents is typically implemented using message queues in shared storage.

> Most of time, you don't need Multi-Agents. Start with a simple solution first.
{: .best-practice }

### Example Agent Communication: Message Queue

Here's a simple example showing how to implement agent communication using `asyncio.Queue`. 
The agent listens for messages, processes them, and continues listening:

```python
class AgentNode(AsyncNode):
    async def prep_async(self, _):
        message_queue = self.params["messages"]
        message = await message_queue.get()
        print(f"Agent received: {message}")
        return message

# Create node and flow
agent = AgentNode()
agent >> agent  # connect to self
flow = AsyncFlow(start=agent)

# Create heartbeat sender
async def send_system_messages(message_queue):
    counter = 0
    messages = [
        "System status: all systems operational",
        "Memory usage: normal",
        "Network connectivity: stable",
        "Processing load: optimal"
    ]
    
    while True:
        message = f"{messages[counter % len(messages)]} | timestamp_{counter}"
        await message_queue.put(message)
        counter += 1
        await asyncio.sleep(1)

async def main():
    message_queue = asyncio.Queue()
    shared = {}
    flow.set_params({"messages": message_queue})
    
    # Run both coroutines
    await asyncio.gather(
        flow.run_async(shared),
        send_system_messages(message_queue)
    )
    
asyncio.run(main())
```

The output:

```
Agent received: System status: all systems operational | timestamp_0
Agent received: Memory usage: normal | timestamp_1
Agent received: Network connectivity: stable | timestamp_2
Agent received: Processing load: optimal | timestamp_3
```

### Interactive Multi-Agent Example: Taboo Game

Here's a more complex example where two agents play the word-guessing game Taboo. 
One agent provides hints while avoiding forbidden words, and another agent tries to guess the target word:

```python
class AsyncHinter(AsyncNode):
    async def prep_async(self, shared):
        guess = await shared["hinter_queue"].get()
        if guess == "GAME_OVER":
            return None
        return shared["target_word"], shared["forbidden_words"], shared.get("past_guesses", [])

    async def exec_async(self, inputs):
        if inputs is None:
            return None
        target, forbidden, past_guesses = inputs
        prompt = f"Generate hint for '{target}'\nForbidden words: {forbidden}"
        if past_guesses:
            prompt += f"\nPrevious wrong guesses: {past_guesses}\nMake hint more specific."
        prompt += "\nUse at most 5 words."
        
        hint = call_llm(prompt)
        print(f"\nHinter: Here's your hint - {hint}")
        return hint

    async def post_async(self, shared, prep_res, exec_res):
        if exec_res is None:
            return "end"
        await shared["guesser_queue"].put(exec_res)
        return "continue"

class AsyncGuesser(AsyncNode):
    async def prep_async(self, shared):
        hint = await shared["guesser_queue"].get()
        return hint, shared.get("past_guesses", [])

    async def exec_async(self, inputs):
        hint, past_guesses = inputs
        prompt = f"Given hint: {hint}, past wrong guesses: {past_guesses}, make a new guess. Directly reply a single word:"
        guess = call_llm(prompt)
        print(f"Guesser: I guess it's - {guess}")
        return guess

    async def post_async(self, shared, prep_res, exec_res):
        if exec_res.lower() == shared["target_word"].lower():
            print("Game Over - Correct guess!")
            await shared["hinter_queue"].put("GAME_OVER")
            return "end"
            
        if "past_guesses" not in shared:
            shared["past_guesses"] = []
        shared["past_guesses"].append(exec_res)
        
        await shared["hinter_queue"].put(exec_res)
        return "continue"

async def main():
    # Set up game
    shared = {
        "target_word": "nostalgia",
        "forbidden_words": ["memory", "past", "remember", "feeling", "longing"],
        "hinter_queue": asyncio.Queue(),
        "guesser_queue": asyncio.Queue()
    }
    
    print("Game starting!")
    print(f"Target word: {shared['target_word']}")
    print(f"Forbidden words: {shared['forbidden_words']}")

    # Initialize by sending empty guess to hinter
    await shared["hinter_queue"].put("")

    # Create nodes and flows
    hinter = AsyncHinter()
    guesser = AsyncGuesser()

    # Set up flows
    hinter_flow = AsyncFlow(start=hinter)
    guesser_flow = AsyncFlow(start=guesser)

    # Connect nodes to themselves
    hinter - "continue" >> hinter
    guesser - "continue" >> guesser

    # Run both agents concurrently
    await asyncio.gather(
        hinter_flow.run_async(shared),
        guesser_flow.run_async(shared)
    )

asyncio.run(main())
```

The Output:

```
Game starting!
Target word: nostalgia
Forbidden words: ['memory', 'past', 'remember', 'feeling', 'longing']

Hinter: Here's your hint - Thinking of childhood summer days
Guesser: I guess it's - popsicle

Hinter: Here's your hint - When childhood cartoons make you emotional
Guesser: I guess it's - nostalgic

Hinter: Here's your hint - When old songs move you
Guesser: I guess it's - memories

Hinter: Here's your hint - That warm emotion about childhood
Guesser: I guess it's - nostalgia
Game Over - Correct guess!
```