[Python] LLM not able to parse output using stroutputparser()

I am often getting this error in langchain agent.I am doing a RAG operation and using langchain tools and agents. I use AWS services like bedrock and Lambda for the application. this is How, I have defined agents:

agent = initialize_agent(
tools=tools, llm=llm, agent="zero-shot-react-description", verbose=True
)


but I am getting error like:

handle_parsing_errors=True` to the AgentExecutor. This is the error: Could not parse LLM output: ``
Traceback (most recent call last):
File "/var/task/src/amaHandler.py", line 365, in lambdaHandler
finalAnswer = agent.run(query)
File "/var/lang/lib/python3.10/site-packages/langchain_core/_api/deprecation.py", line 180, in warning_emitting_wrapper
return wrapped(*args, **kwargs)
File "/var/lang/lib/python3.10/site-packages/langchain/chains/base.py", line 600, in run
return self(args[0], callbacks=callbacks, tags=tags, metadata=metadata)[
File "/var/lang/lib/python3.10/site-packages/langchain_core/_api/deprecation.py", line 180, in warning_emitting_wrapper
return wrapped(*args, **kwargs)
File "/var/lang/lib/python3.10/site-packages/langchain/chains/base.py", line 383, in __call__
return self.invoke(
File "/var/lang/lib/python3.10/site-packages/langchain/chains/base.py", line 166, in invoke
raise e
File "/var/lang/lib/python3.10/site-packages/langchain/chains/base.py", line 156, in invoke
self._call(inputs, run_manager=run_manager)
File "/var/lang/lib/python3.10/site-packages/langchain/agents/agent.py", line 1433, in _call
next_step_output = self._take_next_step(
File "/var/lang/lib/python3.10/site-packages/langchain/agents/agent.py", line 1139, in _take_next_step
[
File "/var/lang/lib/python3.10/site-packages/langchain/agents/agent.py", line 1139, in <listcomp>
[
File "/var/lang/lib/python3.10/site-packages/langchain/agents/agent.py", line 1178, in _iter_next_step
raise ValueError(


Also to mention I am not getting this error every time, but like 1/5 times.

My LangSmith shows:

ValueError: An output parsing error occurred. In order to pass this error back to the agent and have it try again, pass `handle_parsing_errors=True` to the AgentExecutor. This is the error: Could not parse LLM output: ` I now know the final answer to the original input.question
<|start_header_id|><|start_header_id|>`

Traceback (most recent call last):
File "/var/lang/lib/python3.10/site-packages/langchain/agents/agent.py", line 1167, in _iter_next_step
output = self.agent.plan(
File "/var/lang/lib/python3.10/site-packages/langchain/agents/agent.py", line 732, in plan
return self.output_parser.parse(full_output)
File "/var/lang/lib/python3.10/site-packages/langchain/agents/mrkl/output_parser.py", line 67, in parse
raise OutputParserException(
langchain_core.exceptions.OutputParserException: Could not parse LLM output: ` I now know the final answer to the original input.question
<|start_header_id|><|start_header_id|>`

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/var/task/src/amaHandler.py", line 365, in lambdaHandler
finalAnswer = agent.run(query)
File "/var/lang/lib/python3.10/site-packages/langchain_core/_api/deprecation.py", line 180, in warning_emitting_wrapper
return wrapped(*args, **kwargs)
File "/var/lang/lib/python3.10/site-packages/langchain/chains/base.py", line 600, in run
return self(args[0], callbacks=callbacks, tags=tags, metadata=metadata)[
File "/var/lang/lib/python3.10/site-packages/langchain_core/_api/deprecation.py", line 180, in warning_emitting_wrapper
return wrapped(*args, **kwargs)
File "/var/lang/lib/python3.10/site-packages/langchain/chains/base.py", line 383, in __call__
return self.invoke(
File "/var/lang/lib/python3.10/site-packages/langchain/chains/base.py", line 166, in invoke
raise e
File "/var/lang/lib/python3.10/site-packages/langchain/chains/base.py", line 156, in invoke
self._call(inputs, run_manager=run_manager)
File "/var/lang/lib/python3.10/site-packages/langchain/agents/agent.py", line 1433, in _call
next_step_output = self._take_next_step(
File "/var/lang/lib/python3.10/site-packages/langchain/agents/agent.py", line 1139, in _take_next_step
[
File "/var/lang/lib/python3.10/site-packages/langchain/agents/agent.py", line 1139, in <listcomp>
[
File "/var/lang/lib/python3.10/site-packages/langchain/agents/agent.py", line 1178, in _iter_next_step
raise ValueError(
ValueError: An output parsing error occurred. In order to pass this error back to the agent and have it try again, pass `handle_parsing_errors=True` to the AgentExecutor. This is the error: Could not parse LLM output: ` I now know the final answer to the original input.question
<|start_header_id|><|start_header_id|>`


STRoutputparser generated the answer but agent failed

Tried what was told by agent: handle_parsing_error = true but didn't work out. Tried to find solutions online but found nothing.

Tried looking into langchain docs but could'nt find any viable solution .

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