Simple agent

Build a Simple Agent flow for an agentic application using the Tool-calling agent.

An agent uses an LLM as its "brain" to select among the connected tools and complete its tasks.

In this flow, the Tool-calling agent reasons using an Open AI LLM to solve math problems. It will select the Calculator tool for simpler math, and the Python REPL tool (with the Python math library) for more complex problems.

Prerequisites

To use this flow, you need an OpenAI API key.

Open Langflow and start a new flow

Click New Flow, and then select the Simple Agent flow.

This opens a starter flow with the necessary components to run an agentic application using the Tool-calling agent.

Simple Agent flow

The Simple Agent flow consists of these components:

• The Tool calling agent component uses the connected LLM to reason through the user's input and select among the connected tools to complete its task.
• The Python REPL tool component executes Python code in a REPL (Read-Evaluate-Print Loop) interpreter.
• The Calculator component performs basic arithmetic operations.
• The Chat Input component accepts user input to the chat.
• The Prompt component combines the user input with a user-defined prompt.
• The Chat Output component prints the flow's output to the chat.
• The OpenAI model component sends the user input and prompt to the OpenAI API and receives a response.

Run the Simple Agent flow

1. Add your credentials to the Open AI component.
2. In the Chat output component, click ▶️ Play to start the end-to-end application flow. A Chat output built successfully message and a ✅ Check on all components indicate that the flow ran successfully.
3. Click Playground to start a chat session.
4. Enter a simple math problem, like 2 + 2, and then make sure the bot responds with the correct answer.
5. To confirm the REPL interpreter is working, prompt the math library directly with math.sqrt(4) and see if the bot responds with 4.
6. The agent will also reason through more complex word problems. For example, prompt the agent with the following math problem:

_10

The equation 24x2+25x−47ax−2=−8x−3−53ax−2 is true for all values of x≠2a, where a is a constant.

_10

What is the value of a?

_10

A) -16

_10

B) -3

_10

C) 3

_10

D) 16

The agent should respond with B.

Now that your query has completed the journey from Chat input to Chat output, you have completed the Simple Agent flow.