langchain-ai/langgraph

📋 Changes

• release(langgraph): 1.2.5 (#8062)
• fix(langgraph): merge `lc_versions` config metadata (#8052)
• release(cli): 0.4.28 (#8041)
• fix: updateState bug for deltaChannel on empty thread (#8011)
• chore: migrate Python type checking to ty (#8002)
• chore(deps-dev): bump types-requests from 2.33.0.20260408 to 2.33.0.20260518 in /libs/langgraph (#7977)
• chore(deps): bump the minor-and-patch group in /libs/langgraph with 14 updates (#7975)

📋 Changes

• release(cli): 0.4.29 (#8046)
• feat(cli): add support for passing certfile and cert key to run dev server under HTTPS (#8031)

📋 Changes

• release(cli): 0.4.28 (#8041)
• chore(deps): bump starlette from 1.0.0 to 1.0.1 in /libs/cli (#8005)
• chore: migrate Python type checking to ty (#8002)
• chore(deps): bump the minor-and-patch group in /libs/cli with 4 updates (#7962)
• chore(deps): bump typescript from 5.9.3 to 6.0.3 in /libs/cli/js-monorepo-example (#7672)
• chore(deps-dev): bump typescript from 5.9.3 to 6.0.3 in /libs/cli/js-examples in the major group across 1 directory (#7966)
• chore(deps-dev): bump mypy from 1.20.2 to 2.1.0 in /libs/cli in the major group (#7968)
• chore(deps): bump the minor-and-patch group in /libs/cli/js-monorepo-example with 7 updates (#7959)
• + 3 more

📋 Changes

• release(langgraph): 1.2.4 (#7991)
• test(sdk-py): add factory-graph integration test exercising the server factory path (#7978)
• fix(langgraph): keep _on_started backward-compatible with overrides predating cause (#7987)

📋 Changes

• release(langgraph): 1.2.3 (#7945)
• feat(langgraph): wire RemoteGraph.interleave to sdk-py interleave_projections (#7938)
• feat(langgraph): add v3 streaming support to RemoteGraph (#7927)
• feat(langgraph): name tool-dispatched subagents via lc_agent_name (#7928)
• fix(langgraph): rename ProtocolEvent.eventId to event_id to match the wire field (#7942)
• fix(langgraph): merge instead of overwrite in ensure_config for callbacks, tags, metadata, configurable (#7926)
• fix(langgraph): [LSD-1507] Distinguish between user cancelled and other cancellations (#7920)
• fix(cli): bump api bound to 0.10.0 (#7922)
• + 3 more

📋 Changes

• release(sdk-py): 0.4.2 (#7955)
• fix(sdk-py): percent-encode thread_id in v3 stream transport default paths (#7954)

📋 Changes

• release(sdk-py): 0.4.1 (#7944)
• feat(sdk-py): extract stream decoders and add interleave_projections (#7935)
• feat(langgraph): add v3 streaming support to RemoteGraph (#7927)
• fix(sdk-py): make `tools_agent` fake model stateless (#7930)

📋 Changes

• release(sdk-py): 0.4.0 (#7923)
• feat(sdk-py): add thread stream helpers (#7833)
• feat(sdk-py): wire websocket stream selection (#7832)
• feat(sdk-py): add websocket stream transports (#7830)
• feat(sdk-py): harden streaming reconnects (#7829)
• feat(sdk-py): add sync scoped subgraphs (#7828)
• feat(sdk-py): add sync messages and tool calls (#7827)
• feat(sdk-py): add sync thread stream core (#7826)
• + 9 more

📋 Changes

• release(cli): 0.4.27 (#7925)
• fix(cli): pin internal_docker deploy images by digest (#7924)
• fix(cli): bump api bound to 0.10.0 (#7922)
• chore(deps): bump the uv group across 2 directories with 1 update (#7853)
• chore(deps): bump idna from 3.11 to 3.15 in /libs/cli (#7865)
• chore(deps): bump turbo from 2.9.7 to 2.9.14 in /libs/cli/js-monorepo-example (#7868)
• chore(deps): bump langsmith from 0.6.3 to 0.7.1 in /libs/cli/js-monorepo-example (#7854)
• chore(deps): bump langsmith from 0.7.32 to 0.8.0 in /libs/cli (#7791)
• + 3 more

📋 Changes

• chore(langgraph): bump version to 1.2.2 (#7914)
• fix(langgraph): assign stable IDs to id=None BaseMessages before DeltaChannel checkpoint writes (#7913)
• release(checkpoint): 4.1.1 (#7890)

📋 Changes

• release(checkpoint): 4.1.1 (#7890)
• release(sdk-py): 0.3.15 (#7891)
• fix(sdk-py): percent-encode caller-supplied identifiers in URL paths (#7893)
• release(langgraph): 1.2.1 (#7883)
• chore(deps): bump idna from 3.11 to 3.15 in /libs/sdk-py (#7863)
• chore(deps): bump urllib3 from 2.6.3 to 2.7.0 in /libs/sdk-py (#7764)
• chore(deps): bump langsmith from 0.7.31 to 0.8.0 in /libs/sdk-py (#7789)
• release: bump alpha packages to official versions (#7775)
• + 3 more

📋 Changes

• release(checkpoint): 4.1.1 (#7890)
• fix(checkpoint): restrict lc:2 envelope revival to default constructor (#7892)
• chore(deps): bump idna from 3.11 to 3.15 in /libs/checkpoint (#7860)
• chore(deps): bump langsmith from 0.7.31 to 0.8.0 in /libs/checkpoint (#7784)

📋 Changes

• release(langgraph): 1.2.1 (#7883)
• feat(langgraph): add `before_builtins` opt-in for stream transformers (#7882)
• chore(deps): bump idna from 3.11 to 3.15 in /libs/langgraph (#7866)
• fix(langgraph): keep tool results out of v3 messages (#7838)
• chore(deps): bump langsmith from 0.7.31 to 0.8.0 in /libs/langgraph (#7788)

📋 Changes

• release: bump alpha packages to official versions (#7775)
• feat(langgraph): durable error-handler resume across host crashes (#7773)
• feat(langgraph): add set_node_defaults() to StateGraph (#7747)
• chore(deps): bump urllib3 from 2.6.3 to 2.7.0 in /libs/langgraph (#7766)
• chore(deps): bump mistune from 3.2.0 to 3.2.1 in /libs/langgraph (#7733)
• chore(langgraph): bump langchain-core to 1.4.0 (#7767)
• feat(checkpoint): force delta channel snapshot after max supersteps since last snapshot (#7746)
• test(langgraph): de-flake heartbeat progress test (#7735)
• + 7 more

📋 Changes

• release: bump alpha packages to official versions (#7775)
• chore(deps): bump urllib3 from 2.6.3 to 2.7.0 in /libs/prebuilt (#7763)
• chore(langgraph): bump langchain-core to 1.4.0 (#7767)
• chore(deps): bump ty from 0.0.23 to 0.0.33 in /libs/sdk-py (#7666)
• feat(checkpoint-sqlite): override get_delta_channel_history with streaming walk (#7702)
• chore(deps-dev): bump the minor-and-patch group across 1 directory with 3 updates (#7698)
• release: alpha bump (a4) for langgraph, checkpoint, checkpoint-postgres (#7701)
• release: alpha bump langgraph 1.2.0a6 (#7697)

📋 Changes

• release(cli): 0.4.26 (#7772)
• fix(cli): add support for prerelease api_versions (#7771)
• chore(deps): bump the uv group across 2 directories with 1 update (#7749)
• chore(deps): bump urllib3 from 2.6.3 to 2.7.0 in /libs/cli (#7765)
• chore(deps): bump langchain-core from 1.3.0 to 1.3.3 in /libs/cli (#7753)

📋 Changes

• release: bump alpha packages to official versions (#7775)
• chore(deps): bump urllib3 from 2.6.3 to 2.7.0 in /libs/checkpoint-sqlite (#7760)
• chore(deps): bump langchain-core from 1.2.28 to 1.3.3 in /libs/checkpoint-sqlite (#7751)
• chore: remove keepset helper (#7745)
• chore(langgraph): add guide/conformance for delta channel checkpointer (#7736)

📋 Changes

• release: bump alpha packages to official versions (#7775)
• chore(deps): bump urllib3 from 2.6.3 to 2.7.0 in /libs/checkpoint-postgres (#7761)
• chore(deps): bump langchain-core from 1.3.2 to 1.3.3 in /libs/checkpoint-postgres (#7754)
• fix(checkpoint-postgres): add column aliases to seed-blob branch of delta stage-2 UNION ALL (#7728)

📋 Changes

• release: bump alpha packages to official versions (#7775)
• chore(deps): bump urllib3 from 2.6.3 to 2.7.0 in /libs/checkpoint (#7762)
• chore(deps): bump langchain-core from 1.3.2 to 1.3.3 in /libs/checkpoint (#7752)
• feat(checkpoint): force delta channel snapshot after max supersteps since last snapshot (#7746)
• fix(checkpoint): specify allowed_objects in Reviver (#7743)
• chore: remove keepset helper (#7745)
• chore(langgraph): add guide/conformance for delta channel checkpointer (#7736)
• docs(checkpoint): mark DeltaChannel and delta-history APIs as beta (#7732)
• + 3 more

📋 Changes

• release: bump cli version (#7734)
• feat(cli): support studio deploy (#7394)
• chore(deps): bump the minor-and-patch group in /libs/cli with 4 updates (#7674)
• chore(deps): bump the minor-and-patch group in /libs/cli/js-examples with 8 updates (#7673)
• chore(deps): bump the minor-and-patch group in /libs/cli/js-monorepo-example with 7 updates (#7671)
• chore: update x links to langchain_oss (#7645)

📋 Changes

• release(sdk-py): 0.3.14 (#7712)
• feat(sdk-py): add return_minimal to threads update (#7704)
• release: alpha bump (a4) for langgraph, checkpoint, checkpoint-postgres (#7701)
• release: alpha bump langgraph 1.2.0a6 (#7697)
• release: alpha bump prebuilt 1.1.0a2, langgraph 1.2.0a5 (#7682)
• release: alpha bump prebuilt 1.1.0a1, langgraph 1.2.0a4 (#7679)
• feat(langgraph): dispatch stream_events(version='v3') on Pregel (#7677)
• release: alpha bump (a3) for langgraph, checkpoint, checkpoint-postgres (#7678)
• + 19 more

📋 Changes

• feat(checkpoint-sqlite): override get_delta_channel_history with streaming walk (#7702)
• release: alpha bump (a4) for langgraph, checkpoint, checkpoint-postgres (#7701)
• feat: public get_writes_history saver API + delta cadence rework (#7699)
• chore(deps): bump the minor-and-patch group in /libs/checkpoint-sqlite with 2 updates (#7668)
• release: alpha bump (a3) for langgraph, checkpoint, checkpoint-postgres (#7678)
• release: alpha for timers (#7647)
• chore: update x links to langchain_oss (#7645)
• release(checkpoint): 4.0.3 (#7625)
• + 23 more

📋 Changes

• release: alpha bump (a4) for langgraph, checkpoint, checkpoint-postgres (#7701)
• feat: public get_writes_history saver API + delta cadence rework (#7699)

📦 `DeltaChannel` (beta)

• Use `snapshot_frequency=K` to write a full snapshot every K steps and bound read latency:
• ```python
• from typing import Annotated, Sequence
• from typing_extensions import TypedDict
• from langgraph.channels import DeltaChannel
• def list_reducer(messages: list[str], writes: Sequence[list[str]]) -> list[str]:
• return [*messages, *(item for write in writes for item in write)]
• class State(TypedDict):
• + 4 more

📦 Per-node timeouts

• ```python
• from langgraph.types import RetryPolicy, TimeoutPolicy
• builder.add_node(
• "call_model",
• call_model,
• timeout=TimeoutPolicy(run_timeout=120),
• retry_policy=RetryPolicy(max_attempts=3),
• )
• + 22 more

📦 Node-level error handlers

• ```python
• from langgraph.errors import NodeError
• from langgraph.types import Command, RetryPolicy
• def payment_error_handler(state: State, error: NodeError) -> Command:
• return Command(
• update={"status": f"compensated: {error.error}"},
• goto="finalize",
• )
• + 9 more

📦 Graceful shutdown

• ```python
• import signal
• from langgraph.runtime import RunControl
• from langgraph.errors import GraphDrained
• control = RunControl()
• signal.signal(signal.SIGTERM, lambda *_: control.request_drain("sigterm"))
• try:
• result = graph.invoke(inputs, config, control=control)
• + 8 more

✨ New event streaming API (beta)

• ```python
• run = graph.stream_events(input, version="v3")
• for state in run.values: # one snapshot per superstep
• print(state)
• print(run.output) # final state
• print(run.interrupted, run.interrupts)
• ```
• `run.output`, `run.interrupted`, and `run.interrupts` are populated regardless of which transformers are registered, so the "run to completion and read the result" path stays one line.

📦 Per-LLM streams with typed sub-projections

• ```python
• async for chat in graph.astream_events(input, version="v3").messages:
• async for token in chat.text:
• print(token, end="", flush=True)
• tool_calls = await chat.tool_calls.collect()
• final = await chat.output # finalized AIMessage
• ```
• This is the recommended path for token-level streaming to a UI in 1.2. Content-block streaming requires v3 end-to-end, including any inner graphs.

📦 Built-in projections

• | Projection | What it carries |
• | ------------------ | ----------------------------------------------------------------- |
• | `run.values` | full state snapshot per superstep (also drives `run.output` etc.) |
• | `run.messages` | one `ChatModelStream` per LLM call |
• | `run.lifecycle` | subgraph started / completed / failed payloads |
• | `run.subgraphs` | navigation handles for direct-child subgraphs |
• Other channels are opt-in — register them via `compile(transformers=[...])` or the call-site `transformers=` on `stream_events`:
• | Transformer | Adds |
• + 13 more

📦 Custom transformers

• ```python
• from typing import Any
• from langgraph.stream import StreamTransformer, StreamChannel
• class TokenCounter(StreamTransformer):
• """Surface per-call token usage for chat models at the run scope."""
• required_stream_modes = ("messages",)
• def __init__(self, scope: tuple[str, ...] = ()) -> None:
• super().__init__(scope)
• + 22 more

📦 Migration notes

• v3 is opt-in via `version="v3"`; `version="v1"` and `version="v2"` are unchanged.
• The protocol is in beta and may change before stabilization.

📋 Changes

• release: alpha bump (a4) for langgraph, checkpoint, checkpoint-postgres (#7701)
• feat: public get_writes_history saver API + delta cadence rework (#7699)
• chore(deps): bump the minor-and-patch group in /libs/checkpoint-postgres with 2 updates (#7665)

📋 Changes

• release: alpha bump (a4) for langgraph, checkpoint, checkpoint-postgres (#7701)
• feat: public get_writes_history saver API + delta cadence rework (#7699)

📋 Changes

• release: alpha bump prebuilt 1.1.0a2, langgraph 1.2.0a5 (#7682)
• fix(langgraph): coerce dict/str writes in _messages_delta_reducer (#7680)

📋 Changes

• release: alpha bump prebuilt 1.1.0a1, langgraph 1.2.0a4 (#7679)

📋 Changes

• feat(langgraph): dispatch stream_events(version='v3') on Pregel (#7677)
• release: alpha bump (a3) for langgraph, checkpoint, checkpoint-postgres (#7678)
• chore(langgraph): use two phase read to avoid unnecessary data transport (#7660)
• fix(langgraph): make NodeTimeoutError retryable by default (#7659)
• fix(langgraph): arrival-ordered interleave for StreamChannel projections (#7643)
• feat(langgraph): add node-level error handlers (#7233)
• feat: allow graph to graceful shutdown/drain by request (#7274)
• release: alpha for timers (#7647)
• + 17 more

📋 Changes

• release: alpha bump prebuilt 1.1.0a2, langgraph 1.2.0a5 (#7682)
• fix(prebuilt): scope `ToolCallTransformer` projection to its own namespace (#7681)