Hey everyone, been experimenting with both approaches for a client's lead qualification bot. The core question on cost is tricky because it's not just about token price—it's about how many tokens you end up using.
AutoGen's strength is its automated multi-agent conversation, but that's also its cost danger zone. If you're not careful, you can get into long, looping chats between agents that rack up tokens. A simple custom loop using the OpenAI SDK often gives you tighter control.
Here's a barebones example of what I mean by a custom agent loop. It's more work, but you see every API call.
```python
import openai
system_prompt = "You are a lead qualifier. Extract company size and budget."
user_input = "Lead email says they're a startup looking for a basic plan."
response = openai.chat.completions.create(
model="gpt-4o-mini",
messages=[
{"role": "system", "content": system_prompt},
{"role": "user", "content": user_input}
],
max_tokens=100
)
# One call, one cost. You handle the logic flow yourself.
```
With AutoGen, you'd set up an `AssistantAgent` and a `UserProxyAgent`, and the conversation between them to decide on qualification might involve several back-and-forth messages automatically. Each of those messages adds to the token count.
**Key factors that swing the cost:**
* **Orchestration overhead:** AutoGen adds structure prompts and coordination messages.
* **Looping risk:** Custom code avoids unintended agent repetitions.
* **Tool calls:** Both can use functions/tools, but in AutoGen the planning and execution often involve extra turns.
For simple, deterministic workflows—like "take input, run one LLM call, use the output"—a custom SDK script is almost always cheaper. Where AutoGen might save you money is in complex scenarios where building that custom orchestration would be so time-consuming that the dev cost outweighs the slightly higher token cost.
My rule of thumb: if your workflow needs more than two agents or has unpredictable decision paths, try AutoGen but monitor token usage closely. For linear tasks, roll your own.
What's been your experience? Anyone done a direct cost comparison on a similar workflow?