Overview
LangChain Agents is a framework component that enables LLMs to use tools and take actions. It provides structured approaches for building agents that can reason about which tools to use and execute multi-step workflows.
Problem It Solves
Simplifies the development of AI agents by providing abstractions for tool use, memory management, and chain-of-thought reasoning. Reduces boilerplate code when building LLM applications that need to interact with external systems.
Target Audience: Software developers building LLM-powered applications, particularly those needing tool integration, retrieval augmentation, or multi-step reasoning capabilities.
Inputs
- • User query or task
- • Tool definitions and configurations
- • LLM provider credentials
- • Optional: Vector store for memory
- • Optional: Custom prompt templates
Outputs
- • Agent responses
- • Tool execution results
- • Intermediate reasoning steps
- • Structured data outputs
Example Workflow
- 1 Initialize agent with LLM and available tools
- 2 Receive user input or query
- 3 Agent reasons about which tool to use
- 4 Execute selected tool with generated parameters
- 5 Observe tool output and decide next action
- 6 Repeat until task complete or max iterations reached
- 7 Return final response to user
Sample System Prompt
Answer the following questions as best you can. You have access to the following tools:
{tools}
Use the following format:
Question: the input question you must answer
Thought: you should always think about what to do
Action: the action to take, should be one of [{tool_names}]
Action Input: the input to the action
Observation: the result of the action
... (repeat Thought/Action/Observation as needed)
Thought: I now know the final answer
Final Answer: the final answer to the original question
Tools & Technologies
Alternatives
- • LlamaIndex
- • Semantic Kernel
- • Haystack
FAQs
- Is this agent open-source?
- Yes
- Can this agent be self-hosted?
- Yes
- What skill level is required?
- Intermediate
LangChain is one of the most widely adopted frameworks for building LLM applications and provides extensive documentation and community support.