InterruptResumeStateMissingError
langgraph.errors.InterruptResumeStateMissingError
Stack trace
Traceback (most recent call last):
File "app.py", line 42, in <module>
graph.resume_execution(resume_state)
File "/usr/local/lib/python3.9/site-packages/langgraph/graph.py", line 210, in resume_execution
raise InterruptResumeStateMissingError("Resume state data is missing or invalid.")
langgraph.errors.InterruptResumeStateMissingError: Resume state data is missing or invalid. Why it happens
LangGraph requires a valid resume state object to continue execution after an interrupt. This error occurs when the resume state is missing, corrupted, or not passed correctly, preventing the graph from resuming properly.
Detection
Check for the presence and validity of the resume state object before calling resume_execution; log or assert its existence to catch this error early.
Causes & fixes
No resume state object was provided to the resume_execution method.
Ensure that the resume state object returned from the initial interrupt is saved and passed back exactly when resuming the graph.
The resume state object was corrupted or partially overwritten before resuming.
Serialize and deserialize the resume state carefully, using safe formats like JSON or pickle, and validate integrity before resuming.
Incorrect variable or parameter name used when passing the resume state.
Verify that the parameter name matches the expected argument in resume_execution and that the correct variable is passed.
Attempting to resume a graph execution without any prior interrupt or saved state.
Only call resume_execution if an interrupt occurred and a valid resume state was generated; otherwise, start a fresh execution.
Code: broken vs fixed
from langgraph import LangGraph
graph = LangGraph()
# Missing resume_state causes error
resume_state = None
# This line triggers InterruptResumeStateMissingError
graph.resume_execution(resume_state)import os
from langgraph import LangGraph
# Setup environment variables if needed
os.environ['LANGGRAPH_API_KEY'] = os.getenv('LANGGRAPH_API_KEY')
graph = LangGraph()
# Correctly saved resume state from previous interrupt
resume_state = get_saved_resume_state() # Implement this to retrieve saved state
# Pass valid resume state to resume_execution
graph.resume_execution(resume_state)
print("Graph resumed successfully.")Workaround
Wrap resume_execution in try/except InterruptResumeStateMissingError and fallback to restarting the graph execution from scratch if resume state is missing.
Prevention
Implement robust state saving and validation mechanisms immediately after interrupts, and enforce passing valid resume state objects when resuming graph executions.