Update langgraph agent recipe (#513)

recipes/use_cases/agents/langchain/README.md

@@ -1,61 +1,70 @@
 # LangChain <> Llama3 Cookbooks
 
-LLM agents use [planning, memory, and tools](https://lilianweng.github.io/posts/2023-06-23-agent/) to accomplish tasks.
+LLM agents use [planning, memory, and tools](https://lilianweng.github.io/posts/2023-06-23-agent/) to accomplish tasks. Agents can empower Llama 3 with important new capabilities. Here, we will show how to give Llama 3 the ability to perform web search, as well as multi-modality: image generation (text-to-image), image analysis (image-to-text), and voice (text-to-speech) tools!
 
-LangChain offers several different ways to implement agents.
+LangChain offers several different ways to implement agents with Llama 3:
 
-(1) Use [AgentExecutor](https://python.langchain.com/docs/modules/agents/quick_start/) with [tool-calling](https://python.langchain.com/docs/integrations/chat/) versions of Llama 3.
+(1) `ReAct agent` - Uses [AgentExecutor](https://python.langchain.com/docs/modules/agents/quick_start/) with [tool-calling](https://python.langchain.com/docs/integrations/chat/) versions of Llama 3.
 
-(2) Use [LangGraph](https://python.langchain.com/docs/langgraph), a library from LangChain that can be used to build reliable agents with Llama 3.
+(2) `LangGraph tool calling agent` - Uses [LangGraph](https://python.langchain.com/docs/langgraph) with [tool-calling](https://python.langchain.com/docs/integrations/chat/) versions of Llama 3.
+
+(3) `LangGraph custom agent` - Uses [LangGraph](https://python.langchain.com/docs/langgraph) with **any** version of Llama 3 (so long as it supports structured output).
+
+As we move from option (1) to (3) the degree of customization and flexibility increases:
+
+(1) `ReAct agent` using AgentExecutor is a great for getting started quickly with minimal code, but requires a version of Llama 3 with reliable tool-calling, is the least customizable, and uses higher-level AgentExecutor abstraction.
+  
+(2) `LangGraph tool calling agent` is more customizable than (1) because the LLM assistant (planning) and tool call (action) nodes are defined by the user, but it still requires a version of Llama 3 with reliable tool-calling.
+  
+(3) `LangGraph custom agent` does not require a version of Llama 3 with reliable tool-calling and is the most customizable, but requires the most work to implement. 
+
+![langgraph_agent_architectures](https://github.com/rlancemartin/llama-recipes/assets/122662504/5ed2bef0-ae11-4efa-9e88-ab560a4d0022)
 
 ---
 
-### AgentExecutor Agent
+### `ReAct agent`
 
-AgentExecutor is the runtime for an agent. AgentExecutor calls the agent, executes the actions it chooses, passes the action outputs back to the agent, and repeats.
+The AgentExecutor manages the loop of planning, executing tool calls, and processing outputs until an AgentFinish signal is generated, indicating task completion.
 
 Our first notebook, `tool-calling-agent`, shows how to build a [tool calling agent](https://python.langchain.com/docs/modules/agents/agent_types/tool_calling/) with AgentExecutor and Llama 3.
 
-This shows how to build an agent that uses web search, text2image, image2text, and text2speech tools.
-
 --- 
 
-### LangGraph Agent
+### `LangGraph tool calling agent`
 
 [LangGraph](https://python.langchain.com/docs/langgraph) is a library from LangChain that can be used to build reliable agents.
 
-LangGraph can be used to build agents with a few pieces:
-- **Planning:** Define a control flow of steps that you want the agent to take (a graph)
-- **Memory:** Persist information (graph state) across these steps
-- **Tool use:** Modify state at any step
+Our second notebook, `langgraph-tool-calling-agent`, shows an alternative to AgentExecutor for building a Llama 3 powered agent. 
+
+--- 
 
-Our second notebook, `langgraph-agent`, shows an alternative way to AgentExecutor to build a Llama 3 powered agent in LangGraph. 
+### `LangGraph custom agent`
 
-It discusses some of the trade-offs between AgentExecutor and LangGraph. 
+Our third notebook, `langgraph-custom-agent`, shows how to build a Llama 3 powered agent without reliance on tool-calling. 
 
 --- 
 
-### LangGraph RAG Agent
+### `LangGraph RAG Agent`
 
-Our third notebook, `langgraph-rag-agent`, shows how to apply LangGraph to build advanced Llama 3 powered RAG agents that use ideas from 3 papers:
+Our fourth notebook, `langgraph-rag-agent`, shows how to apply LangGraph to build a custom Llama 3 powered RAG agent that use ideas from 3 papers:
 
 * Corrective-RAG (CRAG) [paper](https://arxiv.org/pdf/2401.15884.pdf) uses self-grading on retrieved documents and web-search fallback if documents are not relevant.
 * Self-RAG [paper](https://arxiv.org/abs/2310.11511) adds self-grading on generations for hallucinations and for ability to answer the question.
 * Adaptive RAG [paper](https://arxiv.org/abs/2403.14403) routes queries between different RAG approaches based on their complexity.
 
 We implement each approach as a control flow in LangGraph:
-- **Planning:** The sequence of RAG steps (e.g., retrieval, grading, and generation) that we want the agent to take
-- **Memory:** All the RAG-related information (input question, retrieved documents, etc) that we want to pass between steps
-- **Tool use:** All the tools needed for RAG (e.g., decide web search or vectorstore retrieval based on the question)
+- **Planning:** The sequence of RAG steps (e.g., retrieval, grading, and generation) that we want the agent to take.
+- **Memory:** All the RAG-related information (input question, retrieved documents, etc) that we want to pass between steps.
+- **Tool use:** All the tools needed for RAG (e.g., decide web search or vectorstore retrieval based on the question).
 
 We will build from CRAG (blue, below) to Self-RAG (green) and finally to Adaptive RAG (red):
 
-![Screenshot 2024-05-03 at 10 50 02 AM](https://github.com/rlancemartin/llama-recipes/assets/122662504/ec4aa1cd-3c7e-4cd1-a1e7-7deddc4033a8)
+![langgraph_rag_agent_](https://github.com/rlancemartin/llama-recipes/assets/122662504/ec4aa1cd-3c7e-4cd1-a1e7-7deddc4033a8)
 
 --- 
+ 
+### `Local LangGraph RAG Agent`
 
-### Local LangGraph RAG Agent
-
-Our fourth notebook, `langgraph-rag-agent-local`, shows how to apply LangGraph to build advanced RAG agents using Llama 3 that run locally and reliably.
+Our fifth notebook, `langgraph-rag-agent-local`, shows how to apply LangGraph to build advanced RAG agents using Llama 3 that run locally and reliably.
 
-See this [video overview](https://www.youtube.com/watch?v=sgnrL7yo1TE) for more detail.
+See this [video overview](https://www.youtube.com/watch?v=sgnrL7yo1TE) for more detail on the design of this agent.

scripts/spellcheck_conf/wordlist.txt

@@ -1314,9 +1314,12 @@ AgentExecutor
 LangGraph
 langgraph
 vectorstore
+AgentFinish
+ReAct
+customizable
 Kaggle
 SalesBot
 Weaviate
 MediaGen
 SDXL
-SVD
+SVD