react_parser_stop_tokenTier 1 · 70% confidence
ai-agents-react-parser-stop-to-when-using-llama3-or-similar-llms-with-the-react-a-6f153ec1
agent: ai_agents
When does this happen?
IF When using Llama3 or similar LLMs with the ReAct agent, the model may generate both a parse-able Action and a Final Answer in the same response, leading to an OutputParserException.
How others solved it
THEN Set the LLM's stop token to 'Observation:' to ensure generation stops immediately after the Observation line and does not produce an extraneous Final Answer. Pass the 'stop' parameter when initializing the LLM (e.g., ChatOllama(model='llama3', stop=['Observation:'])). Then use create_react_agent with that LLM.
from langchain_community.chat_models import ChatOllama llm = ChatOllama(model='llama3', stop=['Observation:']) agent_runnable = create_react_agent(llm, tools, prompt)
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