LangGraph changelog: what's new each month
Every stable LangGraph release summarised by month: the highlights, new features, improvements, fixes and anything you need to act on. 3 months covered; the current month updates daily.
October 2026 · so far
2 releases: 1.2.13 → 1.2.14
October brought focused stability improvements to LangGraph, with several fixes addressing checkpoint management and delta channel handling in complex graph scenarios.
Highlights
- Fixed checkpoint replay logic to prevent threads from incorrectly processing abandoned branches.
- Resolved delta channel counter consistency issues across multiple update state paths.
- Improved subgraph delta channel hydration to work correctly with caller-resolved savers.
Fixed
- Forking now occurs before replaying an update checkpoint when the thread has moved past it.
- Update state operations on older checkpoints no longer leak into unrelated branches.
- Delta channel counters are now maintained consistently across every update state path.
- History traversal is skipped for delta channels that were never written to, improving performance.
- Abandoned branches are no longer incorrectly replayed into delta channel forks.
- Subgraph delta channels now hydrate properly when using caller-resolved savers.
September 2026
1 release: 1.2.12
September brought a focused release with improvements to interrupt handling and type safety. The month included dependency updates and bug fixes to maintain stability.
Highlights
- Added responseSchema parameter to interrupt() for better response control
- Fixed type declarations for v3 stream projections
- Multiple dependency updates for security and compatibility
New
- responseSchema parameter in interrupt() method
Improved
- Type safety for v3 stream projections
Fixed
- Type undeclared v3 stream projections
August 2026
1 release: 1.2.11
August brought refinements to LangGraph's tracing and checkpoint capabilities. The month focused on exposing configuration options and fixing delta channel history handling.
Highlights
- TracePolicy is now exposed on AddNode for better control over tracing behavior.
- Checkpoint system improved with fixes to delta channel history collection.
- Dependency updates across the ecosystem for stability and security.
New
- TracePolicy configuration option exposed on AddNode.
Improved
- Delta channel history now correctly collects writes at plain-value seed.
Fixed
- Delta channel history write collection for plain-value seeds in checkpoints.
Summaries are written automatically from the official release notes (full changelog ↗); check the original notes before relying on a detail. LangGraph: pricing, features and alternatives · All changelogs