What is openloops, explained with cars
An AI agent looks a lot like a car: it has an engine, a chassis and a body. If you understand how a car is built, you understand how an agent is built.
Same engine. Same chassis. A different body, a different agent.
First, what is an AI agent?
An AI agent does not just chat: it also does things. It looks up information, uses tools, remembers what happened and decides what to do next. Today, almost every agent is built from three pieces.
Model
The brain. It understands what you ask and decides what to answer or what to do. For example, GPT, Claude or Gemini.
In the car: Engine
Harness
What gives the model hands, memory and rules: tools, context, files and controls.
In the car: Chassis
Loop
How the agent thinks and behaves. It defines what the agent is for.
In the car: Body
Agent
A model mounted on a harness, guided by a loop. That is when it can actually work.
To really understand each piece, let's build a car.
An agent is like a car
A car has three big parts: engine, chassis and body. An agent does too. Tap each part to see what it corresponds to.
In an agent: The AI model
Engine
It provides the power. There are engines with more horsepower and with less, depending on what you will use them for.
The engine: where the power comes from
There are small engines and huge ones, and each is good for a different use. But an engine, no matter how powerful, cannot do much on its own: it needs a chassis to be mounted on.
Change the power and compare.
The engine alone
It runs at full speed, but it goes nowhere.
Engine and chassis
The same power, turned into movement.
It works the same in AI: a very powerful model, on its own, only chats. To act in the real world it needs a harness.
The chassis: the harness
The chassis is the main structure of the car. The engine is mounted on it and, afterwards, the body. In agents, that structure is called a harness.
A chassis has brakes, a transmission and steering: what lets the engine's power reach the real world and lets you control the car. The harness does the same with the model: it gives it the tools and the mechanisms to drive and control itself.
Tap each system.
In an agent: Tools
It takes the power to the wheels. In an agent, these are the tools that turn an idea into a real action.
Example: Checking the status of an order.
The body: the loop
The body defines what the car is for. With the same chassis and the same engine you can have a bus or a cargo truck, depending on the body you mount on it.
It works the same with agents: the same harness with the same model can be a personal assistant or a customer support agent, depending on the loop you attach.
Change the body and watch the behavior change.
Engine
Does not changeThe AI model. It provides the power, and you can swap it without touching anything else.
OpenAI
Chassis
The harnessDoes not changeopenloops. Everything that turns a model into an agent, and it stays the same when you change the engine or the body.
- Saves the chat memory
- Runs tools with retries
- Keeps each user separate
- Tracks usage
Body
The loop. It defines what your agent is for and how it thinks.
Engine: OpenAI 路 Body: PlanExecuteLoop 路 Chassis: openloops
Illustrative simulation.
So, what is openloops?
openloops is an open source framework that gives you two of the three pieces of an agent: the harness and the loops. In other words, the chassis and the bodies.
A chassis that supports any engine and any body.
You can connect the main models to it, even models that run on your own machine, and attach any loop. Build your own combination:
Engine
The AI model. It provides the power, and you can swap it without touching anything else.
Chassis
The harnessopenloops. Everything that turns a model into an agent, and it stays the same when you change the engine or the body.
- Saves the chat memory
- Runs tools with retries
- Keeps each user separate
- Tracks usage
Body
The loop. It defines what your agent is for and how it thinks.
Engine: OpenAI 路 Body: PlanExecuteLoop 路 Chassis: openloops
Illustrative simulation.
Changing the engine or the body does not force you to rebuild the rest.
Ready-made bodies, and the freedom to create your own
openloops already comes with several ready-to-use loops, like bodies you can attach to your chassis. And if none fits what you need, you can design a new one: openloops is open source.
Personal assistant
PlanExecuteLoopPlans the steps and then carries them out. Good for everyday tasks.
Analyst
ReactLoopReasons, acts and observes the result, step by step, until a complex question is solved.
Customer support
CustomerSupportLoopServes your customers: it acknowledges the problem, finds the information and proposes a solution.
Programmer
CodeSpecialistLoopReads code, writes changes and runs the tests to check them.
Your own
Open sourceA new loop for a different use. The code is open: you can write it, modify it and share it.
openloops uses the Apache 2.0 license, free for commercial use too.
Quick glossary
- Agent
- An AI program that does not just chat: it uses tools, remembers and makes decisions to complete a task.
- Model
- The AI brain that understands and generates language. It is the agent's engine.
- Harness
- The structure around the model that gives it tools, memory, context and controls. It is the chassis.
- Loop
- How the agent thinks and acts, step by step. It defines what it is for. It is the body.
- Framework
- A set of ready-made pieces to build something without starting from scratch.
- Open source
- The code is public: you can use it, study it, modify it and share it.
Ready to build your first agent?
Install openloops, pick a loop and connect the model you want.