Simple agent
Build a Simple Agent flow for an agentic application using the Tool-calling agent component.
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. The agent selects the Calculator tool for simple math problems and the URL tool to search a URL for content.
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
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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 URL tool component searches a list of URLs for content.
- 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
- Add your credentials to the Open AI component.
- Click Playground to start a chat session.
- To confirm the tools are connected, ask the agent,
What tools are available to you?
The response is similar to the following:
_10I have access to the following tools:_10Calculator: Perform basic arithmetic operations._10fetch_content: Load and retrieve data from specified URLs._10fetch_content_text: Load and retrieve text data from specified URLs._10as_dataframe: Load and retrieve data in a structured format (dataframe) from specified URLs._10get_current_date: Returns the current date and time in a selected timezone.
- Ask the agent a question. For example, ask it to create a tabletop character using your favorite rules set.
The agent will tell you when it's using the
URL-fetch_content_text
tool to search for rules information, and when it's usingCalculatorComponent-evaluate_expression
to generate attributes with dice rolls. The final output should be similar to this:
_10Final Attributes_10Strength (STR): 10_10Constitution (CON): 12_10Size (SIZ): 14_10Dexterity (DEX): 9_10Intelligence (INT): 11_10Power (POW): 13_10Charisma (CHA): 8
Now that your query has completed the journey from Chat input to Chat output, you have completed the Simple Agent flow.