●Change8

0.5.0

Breaking Changes
📦 langgraphView on GitHub →
⚠ 8 breaking✨ 8 features🐛 6 fixes⚡ 3 deprecations🔧 14 symbols

Summary

LangGraph 0.5 introduces stricter StateGraph schemas, a new NodeBuilder utility, and more granular streaming modes while optimizing checkpoint storage. It serves as a stabilization release ahead of version 1.0, requiring minor API updates for schemas and internal subclassing.

⚠️ Breaking Changes

  • state_schema is now mandatory in StateGraph.__init__. If you were only passing input/output schemas, you must now explicitly provide the state_schema.
  • PregelNode no longer inherits from Runnable. If you were subclassing PregelNode and relying on Runnable methods, you must update your implementation.
  • Removed support for nodes reading a single managed value.
  • Removed add_conditional_edge(..., then=) parameter.
  • Removed MessageGraph, non-state Graph, and UntrackedValue channel.
  • Removed Context channel, SharedValue, and ChannelsManager.
  • Removed postgres shallow checkpointer.
  • Removed Checkpoint.writes and Checkpoint.pending_sends from the checkpoint structure (auto-migrated on load).

Migration Steps

  1. Upgrade the package using pip install -U "langgraph>=0.5".
  2. Update StateGraph initializations to include a mandatory state_schema.
  3. Rename input to input_schema and output to output_schema in graph definitions.
  4. If using custom nodes that subclass PregelNode, ensure they do not rely on Runnable inheritance.
  5. Replace Channel.subscribe_to with NodeBuilder for future-proofing against 1.0.
  6. Rename retry parameters to retry_policy.

✨ New Features

  • New NodeBuilder utility for declarative node creation and channel attachment.
  • Granular streaming modes: 'tasks' and 'checkpoints' can now be toggled individually.
  • stream_mode='debug' is now an alias for ['tasks', 'checkpoints'].
  • JsonPlusSerializer now supports native NumPy array serialization (including Fortran-ordered).
  • Added print_mode argument to invoke and stream methods.
  • Added task masquerading with update state.
  • Automatic migration for legacy 'pending_sends' data in checkpoints.
  • Support for same-name channels and nodes in StateGraph.

🐛 Bug Fixes

  • Fixed bug where Command(update=) could be ignored if followed by a second interrupt.
  • Fixed step_timeout causing ParentCommand/GraphInterrupt exceptions to bubble up incorrectly.
  • Fixed async callback manager tag handling.
  • Fixed FuturesDict callback execution when GCed.
  • Reduced extraneous keys in checkpoint.metadata for smaller storage footprint.
  • Fixed dev server makefile pidfile issue.

🔧 Affected Symbols

StateGraphStateGraph.inputStateGraph.outputStateGraph.state_schemaPregelNodeNodeBuilderChannel.subscribe_toJsonPlusSerializerMessageGraphadd_conditional_edgeCheckpoint.pending_sendsCheckpoint.writesChannelsManagerSharedValue

⚡ Deprecations

  • input and output arguments in StateGraph are deprecated; use input_schema and output_schema instead.
  • Channel.subscribe_to is deprecated; use the new NodeBuilder utility instead (removal scheduled for 1.0).
  • retry argument is deprecated in favor of retry_policy.