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Description
Checked other resources
- This is a bug, not a usage question. For questions, please use the LangChain Forum (https://forum.langchain.com/).
- I added a clear and detailed title that summarizes the issue.
- I read what a minimal reproducible example is (https://stackoverflow.com/help/minimal-reproducible-example).
- I included a self-contained, minimal example that demonstrates the issue INCLUDING all the relevant imports. The code run AS IS to reproduce the issue.
Example Code
import sys
import uuid
from langgraph.types import Command
from typing_extensions import TypedDict, NotRequired
from langgraph.graph import StateGraph, START, END
from langgraph.checkpoint.memory import InMemorySaver
class State(TypedDict):
topic: NotRequired[str]
joke: NotRequired[str]
output: NotRequired[str]
def generate_topic(state: State):
return Command(
update={"topic": "milk"},
goto="write_joke"
)
# return {"topic": "milk"}
def write_joke(state: State):
print(f"write_joke state.get topic is {state.get("topic")}")
if state.get("topic") == "chickens":
return Command(
goto=END
)
else:
return Command(
update={"joke": f"Why did the chicken join a {state['topic']}"},
goto="play_joke"
)
# return {"joke": f"Why did the chicken join a {state['topic']}"}
def play_joke(state: State):
return Command(
update={"output": f"play the joke about {state["topic"]}"},
goto=END
)
# return {"output": f"play the joke about {state["topic"]}"}
# Build workflow
workflow = StateGraph(State)
# Add nodes
workflow.add_node("generate_topic", generate_topic)
workflow.add_node("write_joke", write_joke)
workflow.add_node("play_joke", play_joke)
# Add edges to connect nodes
workflow.add_edge(START, "generate_topic")
# workflow.add_edge("generate_topic", "write_joke")
# workflow.add_edge("write_joke", "play_joke")
# workflow.add_edge("play_joke", END)
# Compile
checkpointer = InMemorySaver()
graph = workflow.compile(checkpointer=checkpointer)
config = {
"configurable": {
"thread_id": uuid.uuid4(),
}
}
state = graph.invoke({}, config)
full_history = list(graph.get_state_history(config))
print("full_history:")
for i, step in enumerate(full_history):
print(f"step {i}:")
print(f"checkpoint_id: {step.config['configurable'].get('checkpoint_id')}")
print(f" time: {step.created_at}")
print(f" values: {step.values}")
print(f"next: {step.next}")
print("---")
selected_state = full_history[2]
print("selected_state:")
print(selected_state.next)
print(selected_state.values)
new_config = graph.update_state(
selected_state.config,
values={"topic": "chickens"},
)
print(new_config)
graph.invoke(None, new_config)
full_history = list(graph.get_state_history(config))
print("full_history:")
for i, step in enumerate(full_history):
print(f"step {i}:")
print(f"checkpoint_id: {step.config['configurable'].get('checkpoint_id')}")
print(f"time: {step.created_at}")
print(f"values: {step.values}")
print(f"next: {step.next}")
print("---")Error Message and Stack Trace (if applicable)
write_joke state.get topic is milk
full_history:
step 0:
checkpoint_id: 1f0afb2b-0c93-66a1-8003-4e60091b7341
time: 2025-10-23T01:50:45.350150+00:00
values: {'topic': 'milk', 'joke': 'Why did the chicken join a milk', 'output': 'play the joke about milk'}
next: ()
---
step 1:
checkpoint_id: 1f0afb2b-0c91-6e12-8002-babaca22cfbd
time: 2025-10-23T01:50:45.349520+00:00
values: {'topic': 'milk', 'joke': 'Why did the chicken join a milk'}
next: ('play_joke',)
---
step 2:
checkpoint_id: 1f0afb2b-0c8f-614c-8001-715a8642b0da
time: 2025-10-23T01:50:45.348376+00:00
values: {'topic': 'milk'}
next: ('write_joke',)
---
step 3:
checkpoint_id: 1f0afb2b-0c8d-6602-8000-6b316f8d4526
time: 2025-10-23T01:50:45.347676+00:00
values: {}
next: ('generate_topic',)
---
step 4:
checkpoint_id: 1f0afb2b-0c8a-688b-bfff-2a840fb00e4a
time: 2025-10-23T01:50:45.346517+00:00
values: {}
next: ('__start__',)
---
selected_state:
('write_joke',)
{'topic': 'milk'}
{'configurable': {'thread_id': 'd5487fd6-7b33-4c0c-ae29-ea6f0fe3f204', 'checkpoint_ns': '', 'checkpoint_id': '1f0afb2b-0c97-6e47-8002-1c22201756cc'}}
full_history:
step 0:
checkpoint_id: 1f0afb2b-0c97-6e47-8002-1c22201756cc
time: 2025-10-23T01:50:45.351982+00:00
values: {'topic': 'chickens', 'joke': 'Why did the chicken join a milk'}
next: ()
---
step 1:
checkpoint_id: 1f0afb2b-0c93-66a1-8003-4e60091b7341
time: 2025-10-23T01:50:45.350150+00:00
values: {'topic': 'milk', 'joke': 'Why did the chicken join a milk', 'output': 'play the joke about milk'}
next: ()
---
step 2:
checkpoint_id: 1f0afb2b-0c91-6e12-8002-babaca22cfbd
time: 2025-10-23T01:50:45.349520+00:00
values: {'topic': 'milk', 'joke': 'Why did the chicken join a milk'}
next: ('play_joke',)
---
step 3:
checkpoint_id: 1f0afb2b-0c8f-614c-8001-715a8642b0da
time: 2025-10-23T01:50:45.348376+00:00
values: {'topic': 'milk'}
next: ('write_joke',)
---
step 4:
checkpoint_id: 1f0afb2b-0c8d-6602-8000-6b316f8d4526
time: 2025-10-23T01:50:45.347676+00:00
values: {}
next: ('generate_topic',)
---
step 5:
checkpoint_id: 1f0afb2b-0c8a-688b-bfff-2a840fb00e4a
time: 2025-10-23T01:50:45.346517+00:00
values: {}
next: ('__start__',)
---Description
- run
graph.update_stateand get a new_config - run
graph.invoke(None, new_config)
graph doesn't run node write_joke and doesn't goto END
is this an expected behavior when usingreturn Commandfor node switch instead ofworkflow.add_edge?
System Info
System Information
OS: Linux
OS Version: #1 SMP PREEMPT_DYNAMIC Thu Jun 5 18:30:46 UTC 2025
Python Version: 3.12.10 (main, Apr 9 2025, 04:03:51) [Clang 20.1.0 ]
Package Information
langchain_core: 0.3.74
langchain: 0.3.26
langchain_community: 0.3.27
langsmith: 0.4.6
langchain_chroma: 0.2.4
langchain_deepseek: 0.1.4
langchain_openai: 0.3.28
langchain_retrive_test: Installed. No version info available.
langchain_tavily: 0.2.10
langchain_test: Installed. No version info available.
langchain_text_splitters: 0.3.8
langgraph_sdk: 0.2.9
Optional packages not installed
langserve
Other Dependencies
aiohttp: 3.12.14
aiohttp<4.0.0,>=3.8.3: Installed. No version info available.
async-timeout<5.0.0,>=4.0.0;: Installed. No version info available.
chromadb>=1.0.9: Installed. No version info available.
dataclasses-json<0.7,>=0.5.7: Installed. No version info available.
httpx: 0.28.1
httpx-sse<1.0.0,>=0.4.0: Installed. No version info available.
httpx>=0.25.2: Installed. No version info available.
jsonpatch<2.0,>=1.33: Installed. No version info available.
langchain-anthropic;: Installed. No version info available.
langchain-aws;: Installed. No version info available.
langchain-azure-ai;: Installed. No version info available.
langchain-cohere;: Installed. No version info available.
langchain-community;: Installed. No version info available.
langchain-core<1.0.0,>=0.3.51: Installed. No version info available.
langchain-core<1.0.0,>=0.3.66: Installed. No version info available.
langchain-core<1.0.0,>=0.3.68: Installed. No version info available.
langchain-core<1.0.0,>=0.3.70: Installed. No version info available.
langchain-core>=0.3.60: Installed. No version info available.
langchain-deepseek;: Installed. No version info available.
langchain-fireworks;: Installed. No version info available.
langchain-google-genai;: Installed. No version info available.
langchain-google-vertexai;: Installed. No version info available.
langchain-groq;: Installed. No version info available.
langchain-huggingface;: Installed. No version info available.
langchain-mistralai;: Installed. No version info available.
langchain-ollama;: Installed. No version info available.
langchain-openai;: Installed. No version info available.
langchain-openai<1.0.0,>=0.3.28: Installed. No version info available.
langchain-perplexity;: Installed. No version info available.
langchain-text-splitters<1.0.0,>=0.3.8: Installed. No version info available.
langchain-together;: Installed. No version info available.
langchain-xai;: Installed. No version info available.
langchain<1.0.0,>=0.3.26: Installed. No version info available.
langsmith-pyo3: Installed. No version info available.
langsmith>=0.1.125: Installed. No version info available.
langsmith>=0.1.17: Installed. No version info available.
langsmith>=0.3.45: Installed. No version info available.
numpy>=1.26.0;: Installed. No version info available.
numpy>=1.26.2;: Installed. No version info available.
numpy>=2.1.0;: Installed. No version info available.
openai-agents: Installed. No version info available.
openai<2.0.0,>=1.86.0: Installed. No version info available.
opentelemetry-api: 1.35.0
opentelemetry-exporter-otlp-proto-http: Installed. No version info available.
opentelemetry-sdk: 1.35.0
orjson: 3.11.0
orjson>=3.10.1: Installed. No version info available.
packaging: 25.0
packaging>=23.2: Installed. No version info available.
pydantic: 2.11.7
pydantic-settings<3.0.0,>=2.4.0: Installed. No version info available.
pydantic<3.0.0,>=2.7.4: Installed. No version info available.
pydantic>=2.7.4: Installed. No version info available.
pytest: Installed. No version info available.
PyYAML>=5.3: Installed. No version info available.
requests: 2.32.4
requests-toolbelt: 1.0.0
requests<3,>=2: Installed. No version info available.
rich: 14.0.0
SQLAlchemy<3,>=1.4: Installed. No version info available.
tenacity!=8.4.0,<10,>=8.1.0: Installed. No version info available.
tenacity!=8.4.0,<10.0.0,>=8.1.0: Installed. No version info available.
tiktoken<1,>=0.7: Installed. No version info available.
typing-extensions>=4.7: Installed. No version info available.
zstandard: 0.23.0