chore: remove unnecessary missing-typed-dict-key suppression

Co-authored-by: Cursor <cursoragent@cursor.com>

libs/checkpoint-conformance/README.md

@@ -64,6 +64,8 @@ The suite tests **base** capabilities (required) and **extended** capabilities (
 | `copy_thread` | no | `acopy_thread` |
 | `prune` | no | `aprune` |
 | `delta_channel_history` | no | `aget_delta_channel_history` |
+| `delta_channel_keepset` | no | `aget_delta_channel_keepset` |
+| `delta_channel_reconstruction` | no | `aput` |
 
 Extended capabilities are detected by checking whether the method is overridden from `BaseCheckpointSaver`. If not overridden, those tests are skipped.
 

libs/checkpoint-conformance/langgraph/checkpoint/conformance/capabilities.py

@@ -24,6 +24,8 @@ class Capability(str, Enum):
     COPY_THREAD = "copy_thread"
     PRUNE = "prune"
     DELTA_CHANNEL_HISTORY = "delta_channel_history"
+    DELTA_CHANNEL_KEEPSET = "delta_channel_keepset"
+    DELTA_CHANNEL_RECONSTRUCTION = "delta_channel_reconstruction"
 
 
 # Capabilities that every checkpointer must support.
@@ -44,6 +46,8 @@ EXTENDED_CAPABILITIES = frozenset(
         Capability.COPY_THREAD,
         Capability.PRUNE,
         Capability.DELTA_CHANNEL_HISTORY,
+        Capability.DELTA_CHANNEL_KEEPSET,
+        Capability.DELTA_CHANNEL_RECONSTRUCTION,
     }
 )
 
@@ -60,6 +64,8 @@ _CAPABILITY_METHOD_MAP: dict[Capability, str] = {
     Capability.COPY_THREAD: "acopy_thread",
     Capability.PRUNE: "aprune",
     Capability.DELTA_CHANNEL_HISTORY: "aget_delta_channel_history",
+    Capability.DELTA_CHANNEL_KEEPSET: "aget_tuple",
+    Capability.DELTA_CHANNEL_RECONSTRUCTION: "aput",
 }
 
 

libs/checkpoint-conformance/langgraph/checkpoint/conformance/spec/__init__.py

@@ -12,6 +12,12 @@ from langgraph.checkpoint.conformance.spec.test_delete_thread import (
 from langgraph.checkpoint.conformance.spec.test_delta_channel_history import (
     run_delta_channel_history_tests,
 )
+from langgraph.checkpoint.conformance.spec.test_delta_channel_keepset import (
+    run_delta_channel_keepset_tests,
+)
+from langgraph.checkpoint.conformance.spec.test_delta_channel_reconstruction import (
+    run_delta_channel_reconstruction_tests,
+)
 from langgraph.checkpoint.conformance.spec.test_get_tuple import run_get_tuple_tests
 from langgraph.checkpoint.conformance.spec.test_list import run_list_tests
 from langgraph.checkpoint.conformance.spec.test_prune import run_prune_tests
@@ -28,4 +34,6 @@ __all__ = [
     "run_copy_thread_tests",
     "run_prune_tests",
     "run_delta_channel_history_tests",
+    "run_delta_channel_keepset_tests",
+    "run_delta_channel_reconstruction_tests",
 ]

libs/checkpoint-conformance/langgraph/checkpoint/conformance/spec/test_delta_channel_keepset.py

@@ -0,0 +1,172 @@
+"""DELTA_CHANNEL_KEEPSET capability tests — aget_delta_channel_keepset contract."""
+
+from __future__ import annotations
+
+import traceback
+from collections.abc import Callable
+from uuid import uuid4
+
+from langgraph.checkpoint.base import BaseCheckpointSaver
+
+from langgraph.checkpoint.conformance.spec._delta_fixtures import build_delta_chain
+
+
+async def test_keepset_empty_channels_returns_target_only(
+    saver: BaseCheckpointSaver,
+) -> None:
+    """Empty channels → keep-set is just {target_id}."""
+    tid = str(uuid4())
+    configs = await build_delta_chain(
+        saver, thread_id=tid, channel="ch", snapshots_at_steps=[0], total_steps=4
+    )
+    head = configs[-1]
+    keep = await saver.aget_delta_channel_keepset(config=head, channels=[])
+    head_id = head["configurable"]["checkpoint_id"]
+    assert keep == {head_id}, f"Expected only target, got {keep}"
+
+
+async def test_keepset_snapshot_at_target(
+    saver: BaseCheckpointSaver,
+) -> None:
+    """When target itself has a snapshot, keep-set is just {target_id}."""
+    tid = str(uuid4())
+    configs = await build_delta_chain(
+        saver,
+        thread_id=tid,
+        channel="ch",
+        snapshots_at_steps=[0, 3],
+        total_steps=4,
+    )
+    head = configs[3]
+    keep = await saver.aget_delta_channel_keepset(config=head, channels=["ch"])
+    head_id = head["configurable"]["checkpoint_id"]
+    assert keep == {head_id}, f"Snapshot at target should yield only target, got {keep}"
+
+
+async def test_keepset_snapshot_n_back(
+    saver: BaseCheckpointSaver,
+) -> None:
+    """Snapshot N steps back → target + intermediates + snapshot ancestor."""
+    tid = str(uuid4())
+    configs = await build_delta_chain(
+        saver, thread_id=tid, channel="ch", snapshots_at_steps=[0], total_steps=5
+    )
+    head = configs[-1]
+    keep = await saver.aget_delta_channel_keepset(config=head, channels=["ch"])
+    expected_ids = {c["configurable"]["checkpoint_id"] for c in configs}
+    assert keep == expected_ids, f"Expected all ancestors, got {keep}"
+
+
+async def test_keepset_multi_channel_union(
+    saver: BaseCheckpointSaver,
+) -> None:
+    """Multi-channel keep-set is the union (max chain per channel)."""
+    tid = str(uuid4())
+    from langgraph.checkpoint.base import Checkpoint
+    from langgraph.checkpoint.base.id import uuid6
+    from langgraph.checkpoint.serde.types import _DeltaSnapshot
+
+    from langgraph.checkpoint.conformance.test_utils import generate_metadata
+
+    configs: list = []
+    parent_cfg = None
+    for step in range(6):
+        config = {"configurable": {"thread_id": tid, "checkpoint_ns": ""}}
+        if parent_cfg:
+            config["configurable"]["checkpoint_id"] = parent_cfg["configurable"][
+                "checkpoint_id"
+            ]
+        cv: dict = {}
+        cvs: dict = {}
+        # Channel "a" has snapshot at step 3 (recent)
+        if step == 3:
+            cv["a"] = _DeltaSnapshot("snap_a")
+            cvs["a"] = step + 1
+        # Channel "b" has snapshot at step 1 (further back)
+        if step == 1:
+            cv["b"] = _DeltaSnapshot("snap_b")
+            cvs["b"] = step + 1
+        cp = Checkpoint(
+            v=1,
+            id=str(uuid6(clock_seq=-1)),
+            ts="",
+            channel_values=cv,
+            channel_versions=cvs,
+            versions_seen={},
+            updated_channels=None,
+        )
+        parent_cfg = await saver.aput(config, cp, generate_metadata(step=step), cvs)
+        configs.append(parent_cfg)
+
+    head = configs[-1]
+    keep = await saver.aget_delta_channel_keepset(config=head, channels=["a", "b"])
+    # Union: b needs back to step 1, so steps 1..5 (all except step 0) plus head
+    expected_ids = {c["configurable"]["checkpoint_id"] for c in configs[1:]}
+    expected_ids.add(head["configurable"]["checkpoint_id"])
+    assert keep == expected_ids, f"Expected union, got {keep} vs {expected_ids}"
+
+
+async def test_keepset_walk_to_root(
+    saver: BaseCheckpointSaver,
+) -> None:
+    """No snapshot anywhere → entire chain to root is in keep-set."""
+    tid = str(uuid4())
+    configs = await build_delta_chain(
+        saver, thread_id=tid, channel="ch", snapshots_at_steps=[], total_steps=4
+    )
+    head = configs[-1]
+    keep = await saver.aget_delta_channel_keepset(config=head, channels=["ch"])
+    all_ids = {c["configurable"]["checkpoint_id"] for c in configs}
+    assert keep == all_ids, f"Expected full chain, got {keep}"
+
+
+async def test_keepset_deterministic(
+    saver: BaseCheckpointSaver,
+) -> None:
+    """Same inputs return identical sets."""
+    tid = str(uuid4())
+    configs = await build_delta_chain(
+        saver, thread_id=tid, channel="ch", snapshots_at_steps=[0], total_steps=5
+    )
+    head = configs[-1]
+    keep1 = await saver.aget_delta_channel_keepset(config=head, channels=["ch"])
+    keep2 = await saver.aget_delta_channel_keepset(config=head, channels=["ch"])
+    assert keep1 == keep2
+
+
+ALL_DELTA_CHANNEL_KEEPSET_TESTS = [
+    test_keepset_empty_channels_returns_target_only,
+    test_keepset_snapshot_at_target,
+    test_keepset_snapshot_n_back,
+    test_keepset_multi_channel_union,
+    test_keepset_walk_to_root,
+    test_keepset_deterministic,
+]
+
+
+async def run_delta_channel_keepset_tests(
+    saver: BaseCheckpointSaver,
+    on_test_result: Callable[[str, str, bool, str | None], None] | None = None,
+) -> tuple[int, int, list[str]]:
+    """Run all delta_channel_keepset tests. Returns (passed, failed, failure_names)."""
+    passed = 0
+    failed = 0
+    failures: list[str] = []
+    for test_fn in ALL_DELTA_CHANNEL_KEEPSET_TESTS:
+        try:
+            await test_fn(saver)
+            passed += 1
+            if on_test_result:
+                on_test_result("delta_channel_keepset", test_fn.__name__, True, None)
+        except Exception:
+            failed += 1
+            msg = f"{test_fn.__name__}: {traceback.format_exc()}"
+            failures.append(msg)
+            if on_test_result:
+                on_test_result(
+                    "delta_channel_keepset",
+                    test_fn.__name__,
+                    False,
+                    traceback.format_exc(),
+                )
+    return passed, failed, failures

libs/checkpoint-conformance/langgraph/checkpoint/conformance/spec/test_delta_channel_reconstruction.py

@@ -0,0 +1,164 @@
+"""DELTA_CHANNEL_RECONSTRUCTION capability tests — end-to-end round-trip.
+
+Exercises: aput + aput_writes + aget_delta_channel_history + reconstruction.
+This catches the most common silent-corruption mode: failing to round-trip
+`_DeltaSnapshot` blobs through serialization.
+
+NOTE: This test does NOT import from `langgraph` (which is not a dependency
+of checkpoint-conformance). Instead it inlines a minimal reconstruction
+equivalent: seed + fold writes through a simple list-append reducer.
+"""
+
+from __future__ import annotations
+
+import traceback
+from collections.abc import Callable
+from typing import Any
+from uuid import uuid4
+
+from langgraph.checkpoint.base import BaseCheckpointSaver
+
+from langgraph.checkpoint.conformance.spec._delta_fixtures import build_delta_chain
+
+
+def _reconstruct(seed: Any, writes: list) -> list:
+    """Minimal DeltaChannel reconstruction: list-append reducer.
+
+    Mirrors DeltaChannel.from_checkpoint(seed) + replay_writes(writes).
+    """
+    from langgraph.checkpoint.serde.types import _DeltaSnapshot
+
+    if seed is None:
+        base: list = []
+    elif isinstance(seed, _DeltaSnapshot):
+        base = list(seed.value)
+    else:
+        base = list(seed)
+    for _task_id, _ch, value in writes:
+        base = base + value
+    return base
+
+
+async def test_reconstruction_basic(
+    saver: BaseCheckpointSaver,
+) -> None:
+    """Reconstruct delta channel value from history matches expected."""
+    tid = str(uuid4())
+    # 5 steps: snapshot at 0 (value=[0]), writes at 1,2,3,4.
+    # Head = step 4. Walk from parent (step 3) collects writes 1,2,3.
+    configs = await build_delta_chain(
+        saver,
+        thread_id=tid,
+        channel="msgs",
+        snapshots_at_steps=[0],
+        total_steps=5,
+        write_value_fn=lambda step: [step],
+    )
+    head = configs[-1]
+    result = await saver.aget_delta_channel_history(config=head, channels=["msgs"])
+    history = result["msgs"]
+
+    seed = history.get("seed")
+    reconstructed = _reconstruct(seed, history["writes"])
+
+    # seed=[0] from step 0, writes from steps 1,2,3
+    expected = [0] + [1] + [2] + [3]
+    assert reconstructed == expected, (
+        f"Reconstructed {reconstructed} != expected {expected}"
+    )
+
+
+async def test_reconstruction_mid_chain_snapshot(
+    saver: BaseCheckpointSaver,
+) -> None:
+    """Reconstruction works when snapshot is mid-chain."""
+    tid = str(uuid4())
+    # 6 steps: snapshots at 0 and 3, writes at 1,2,4,5.
+    # Head = step 5. Walk from step 4 stops at step 3 (snapshot).
+    # Collects writes from step 4.
+    configs = await build_delta_chain(
+        saver,
+        thread_id=tid,
+        channel="msgs",
+        snapshots_at_steps=[0, 3],
+        total_steps=6,
+        write_value_fn=lambda step: [step],
+    )
+    head = configs[-1]
+    result = await saver.aget_delta_channel_history(config=head, channels=["msgs"])
+    history = result["msgs"]
+
+    seed = history.get("seed")
+    reconstructed = _reconstruct(seed, history["writes"])
+
+    # Snapshot at step 3 = [3], write from step 4
+    expected = [3] + [4]
+    assert reconstructed == expected, (
+        f"Reconstructed {reconstructed} != expected {expected}"
+    )
+
+
+async def test_reconstruction_no_snapshot(
+    saver: BaseCheckpointSaver,
+) -> None:
+    """Reconstruction from root (no snapshot) gives all writes accumulated."""
+    tid = str(uuid4())
+    # 4 steps: no snapshot, writes at 0,1,2,3.
+    # Head = step 3. Walk from step 2 collects writes 0,1,2.
+    configs = await build_delta_chain(
+        saver,
+        thread_id=tid,
+        channel="msgs",
+        snapshots_at_steps=[],
+        total_steps=4,
+        write_value_fn=lambda step: [step],
+    )
+    head = configs[-1]
+    result = await saver.aget_delta_channel_history(config=head, channels=["msgs"])
+    history = result["msgs"]
+
+    seed = history.get("seed")
+    reconstructed = _reconstruct(seed, history["writes"])
+
+    # No seed → start empty, writes from steps 0,1,2
+    expected = [0] + [1] + [2]
+    assert reconstructed == expected, (
+        f"Reconstructed {reconstructed} != expected {expected}"
+    )
+
+
+ALL_DELTA_CHANNEL_RECONSTRUCTION_TESTS = [
+    test_reconstruction_basic,
+    test_reconstruction_mid_chain_snapshot,
+    test_reconstruction_no_snapshot,
+]
+
+
+async def run_delta_channel_reconstruction_tests(
+    saver: BaseCheckpointSaver,
+    on_test_result: Callable[[str, str, bool, str | None], None] | None = None,
+) -> tuple[int, int, list[str]]:
+    """Run all reconstruction tests. Returns (passed, failed, failure_names)."""
+    passed = 0
+    failed = 0
+    failures: list[str] = []
+    for test_fn in ALL_DELTA_CHANNEL_RECONSTRUCTION_TESTS:
+        try:
+            await test_fn(saver)
+            passed += 1
+            if on_test_result:
+                on_test_result(
+                    "delta_channel_reconstruction", test_fn.__name__, True, None
+                )
+        except Exception:
+            failed += 1
+            msg = f"{test_fn.__name__}: {traceback.format_exc()}"
+            failures.append(msg)
+            if on_test_result:
+                on_test_result(
+                    "delta_channel_reconstruction",
+                    test_fn.__name__,
+                    False,
+                    traceback.format_exc(),
+                )
+    return passed, failed, failures

libs/checkpoint-conformance/langgraph/checkpoint/conformance/validate.py

@@ -22,6 +22,12 @@ from langgraph.checkpoint.conformance.spec.test_delete_thread import (
 from langgraph.checkpoint.conformance.spec.test_delta_channel_history import (
     run_delta_channel_history_tests,
 )
+from langgraph.checkpoint.conformance.spec.test_delta_channel_keepset import (
+    run_delta_channel_keepset_tests,
+)
+from langgraph.checkpoint.conformance.spec.test_delta_channel_reconstruction import (
+    run_delta_channel_reconstruction_tests,
+)
 from langgraph.checkpoint.conformance.spec.test_get_tuple import run_get_tuple_tests
 from langgraph.checkpoint.conformance.spec.test_list import run_list_tests
 from langgraph.checkpoint.conformance.spec.test_prune import run_prune_tests
@@ -39,6 +45,8 @@ _RUNNERS = {
     Capability.COPY_THREAD: run_copy_thread_tests,
     Capability.PRUNE: run_prune_tests,
     Capability.DELTA_CHANNEL_HISTORY: run_delta_channel_history_tests,
+    Capability.DELTA_CHANNEL_KEEPSET: run_delta_channel_keepset_tests,
+    Capability.DELTA_CHANNEL_RECONSTRUCTION: run_delta_channel_reconstruction_tests,
 }
 
 

libs/checkpoint-conformance/uv.lock

@@ -279,7 +279,7 @@ wheels = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.1.0"
+version = "4.1.0a4"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },

libs/checkpoint-postgres/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "langgraph-checkpoint-postgres"
-version = "3.1.0"
+version = "3.1.0a4"
 description = "Library with a Postgres implementation of LangGraph checkpoint saver."
 authors = []
 requires-python = ">=3.10"
@@ -12,7 +12,7 @@ readme = "README.md"
 license = "MIT"
 license-files = ['LICENSE']
 dependencies = [
-  "langgraph-checkpoint>=4.1.0,<5.0.0",
+  "langgraph-checkpoint>=4.1.0a4,<5.0.0",
   "orjson>=3.11.5",
   "psycopg>=3.2.0",
   "psycopg-pool>=3.2.0",

libs/checkpoint-postgres/uv.lock

@@ -244,7 +244,7 @@ wheels = [
 
 [[package]]
 name = "langchain-core"
-version = "1.3.3"
+version = "1.3.2"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "jsonpatch" },
@@ -257,9 +257,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "uuid-utils" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/d3/ae/8b74458fc3850ec3d150eb9f45e857db129dafa801fb5cf173dfc9f8bbf3/langchain_core-1.3.3.tar.gz", hash = "sha256:fa510a5db8efdc0c6ff41c0939fb5c00a0183c11f6b84233e892e3227ff69182", size = 915041, upload-time = "2026-05-05T19:02:36.612Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/a8/03/7219502e8ca728d65eb44d7a3eb60239230742a70dbfc9241b9bfd61c4ab/langchain_core-1.3.2.tar.gz", hash = "sha256:fd7a50b2f28ba561fd9d7f5d2760bc9e06cf00cdf820a3ccafe88a94ffa8d5b7", size = 911813, upload-time = "2026-04-24T15:49:23.699Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/1f/01/4771b7ab2af1d1aba5b710bd8f13d9225c609425214b357590a17b01be77/langchain_core-1.3.3-py3-none-any.whl", hash = "sha256:18aae8506f37da7f74398492279a7d6efcee4f8e23c4c41c7af080eeb7ef7bd1", size = 543857, upload-time = "2026-05-05T19:02:34.52Z" },
+    { url = "https://files.pythonhosted.org/packages/7d/d5/8fa4431007cbb7cfed7590f4d6a5dea3ad724f4174d248f6642ef5ce7d05/langchain_core-1.3.2-py3-none-any.whl", hash = "sha256:d44a66127f9f8db735bdfd0ab9661bccb47a97113cfd3f2d89c74864422b7274", size = 542390, upload-time = "2026-04-24T15:49:21.991Z" },
 ]
 
 [[package]]
@@ -276,7 +276,7 @@ wheels = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.1.0"
+version = "4.1.0a4"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },
@@ -324,7 +324,7 @@ test = [
 
 [[package]]
 name = "langgraph-checkpoint-postgres"
-version = "3.1.0"
+version = "3.1.0a4"
 source = { editable = "." }
 dependencies = [
     { name = "langgraph-checkpoint" },
@@ -1234,11 +1234,11 @@ wheels = [
 
 [[package]]
 name = "urllib3"
-version = "2.7.0"
+version = "2.6.3"
 source = { registry = "https://pypi.org/simple" }
-sdist = { url = "https://files.pythonhosted.org/packages/53/0c/06f8b233b8fd13b9e5ee11424ef85419ba0d8ba0b3138bf360be2ff56953/urllib3-2.7.0.tar.gz", hash = "sha256:231e0ec3b63ceb14667c67be60f2f2c40a518cb38b03af60abc813da26505f4c", size = 433602, upload-time = "2026-05-07T16:13:18.596Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/c7/24/5f1b3bdffd70275f6661c76461e25f024d5a38a46f04aaca912426a2b1d3/urllib3-2.6.3.tar.gz", hash = "sha256:1b62b6884944a57dbe321509ab94fd4d3b307075e0c2eae991ac71ee15ad38ed", size = 435556, upload-time = "2026-01-07T16:24:43.925Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/7f/3e/5db95bcf282c52709639744ca2a8b149baccf648e39c8cc87553df9eae0c/urllib3-2.7.0-py3-none-any.whl", hash = "sha256:9fb4c81ebbb1ce9531cce37674bbc6f1360472bc18ca9a553ede278ef7276897", size = 131087, upload-time = "2026-05-07T16:13:17.151Z" },
+    { url = "https://files.pythonhosted.org/packages/39/08/aaaad47bc4e9dc8c725e68f9d04865dbcb2052843ff09c97b08904852d84/urllib3-2.6.3-py3-none-any.whl", hash = "sha256:bf272323e553dfb2e87d9bfd225ca7b0f467b919d7bbd355436d3fd37cb0acd4", size = 131584, upload-time = "2026-01-07T16:24:42.685Z" },
 ]
 
 [[package]]

libs/checkpoint-sqlite/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "langgraph-checkpoint-sqlite"
-version = "3.1.0"
+version = "3.1.0a1"
 description = "Library with a SQLite implementation of LangGraph checkpoint saver."
 authors = []
 requires-python = ">=3.10"
@@ -12,7 +12,7 @@ readme = "README.md"
 license = "MIT"
 license-files = ['LICENSE']
 dependencies = [
-    "langgraph-checkpoint>=4.1.0,<5.0.0",
+    "langgraph-checkpoint>=4.1.0a4,<5.0.0",
     "aiosqlite>=0.20",
     "sqlite-vec>=0.1.6",
 ]

libs/checkpoint-sqlite/tests/test_conformance_delta.py

@@ -27,6 +27,8 @@ async def test_delta_channel_conformance():
         sqlite_saver,
         capabilities={
             "delta_channel_history",
+            "delta_channel_keepset",
+            "delta_channel_reconstruction",
         },
     )
     for cap, result in report.results.items():

libs/checkpoint-sqlite/uv.lock

@@ -253,11 +253,10 @@ wheels = [
 
 [[package]]
 name = "langchain-core"
-version = "1.3.3"
+version = "1.2.28"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "jsonpatch" },
-    { name = "langchain-protocol" },
     { name = "langsmith" },
     { name = "packaging" },
     { name = "pydantic" },
@@ -266,26 +265,14 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "uuid-utils" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/d3/ae/8b74458fc3850ec3d150eb9f45e857db129dafa801fb5cf173dfc9f8bbf3/langchain_core-1.3.3.tar.gz", hash = "sha256:fa510a5db8efdc0c6ff41c0939fb5c00a0183c11f6b84233e892e3227ff69182", size = 915041, upload-time = "2026-05-05T19:02:36.612Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/f8/a4/317a1a3ac1df33a64adb3670bf88bbe3b3d5baa274db6863a979db472897/langchain_core-1.2.28.tar.gz", hash = "sha256:271a3d8bd618f795fdeba112b0753980457fc90537c46a0c11998516a74dc2cb", size = 846119, upload-time = "2026-04-08T18:19:34.867Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/1f/01/4771b7ab2af1d1aba5b710bd8f13d9225c609425214b357590a17b01be77/langchain_core-1.3.3-py3-none-any.whl", hash = "sha256:18aae8506f37da7f74398492279a7d6efcee4f8e23c4c41c7af080eeb7ef7bd1", size = 543857, upload-time = "2026-05-05T19:02:34.52Z" },
-]
-
-[[package]]
-name = "langchain-protocol"
-version = "0.0.15"
-source = { registry = "https://pypi.org/simple" }
-dependencies = [
-    { name = "typing-extensions" },
-]
-sdist = { url = "https://files.pythonhosted.org/packages/4f/24/9777489d6fbbee64af0c8f96d4f840239c408cf694f3394672807dafc490/langchain_protocol-0.0.15.tar.gz", hash = "sha256:9ab2d11ee73944754f10e037e717098d3a6796f0e58afa9cadda6154e7655ade", size = 5862, upload-time = "2026-05-01T22:30:04.748Z" }
-wheels = [
-    { url = "https://files.pythonhosted.org/packages/1d/7a/9c97a7b9cbe4c5dc6a44cdb1545450c28f0c8ce89b9c1f0ee7fbad896263/langchain_protocol-0.0.15-py3-none-any.whl", hash = "sha256:461eb794358f83d5e42635a5797799ffec7b4702314e34edf73ac21e75d3ef79", size = 6982, upload-time = "2026-05-01T22:30:03.877Z" },
+    { url = "https://files.pythonhosted.org/packages/a8/92/32f785f077c7e898da97064f113c73fbd9ad55d1e2169cf3a391b183dedb/langchain_core-1.2.28-py3-none-any.whl", hash = "sha256:80764232581eaf8057bcefa71dbf8adc1f6a28d257ebd8b95ba9b8b452e8c6ac", size = 508727, upload-time = "2026-04-08T18:19:32.823Z" },
 ]
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.1.0"
+version = "4.1.0a4"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },
@@ -333,7 +320,7 @@ test = [
 
 [[package]]
 name = "langgraph-checkpoint-sqlite"
-version = "3.1.0"
+version = "3.1.0a1"
 source = { editable = "." }
 dependencies = [
     { name = "aiosqlite" },
@@ -1161,11 +1148,11 @@ wheels = [
 
 [[package]]
 name = "urllib3"
-version = "2.7.0"
+version = "2.6.3"
 source = { registry = "https://pypi.org/simple" }
-sdist = { url = "https://files.pythonhosted.org/packages/53/0c/06f8b233b8fd13b9e5ee11424ef85419ba0d8ba0b3138bf360be2ff56953/urllib3-2.7.0.tar.gz", hash = "sha256:231e0ec3b63ceb14667c67be60f2f2c40a518cb38b03af60abc813da26505f4c", size = 433602, upload-time = "2026-05-07T16:13:18.596Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/c7/24/5f1b3bdffd70275f6661c76461e25f024d5a38a46f04aaca912426a2b1d3/urllib3-2.6.3.tar.gz", hash = "sha256:1b62b6884944a57dbe321509ab94fd4d3b307075e0c2eae991ac71ee15ad38ed", size = 435556, upload-time = "2026-01-07T16:24:43.925Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/7f/3e/5db95bcf282c52709639744ca2a8b149baccf648e39c8cc87553df9eae0c/urllib3-2.7.0-py3-none-any.whl", hash = "sha256:9fb4c81ebbb1ce9531cce37674bbc6f1360472bc18ca9a553ede278ef7276897", size = 131087, upload-time = "2026-05-07T16:13:17.151Z" },
+    { url = "https://files.pythonhosted.org/packages/39/08/aaaad47bc4e9dc8c725e68f9d04865dbcb2052843ff09c97b08904852d84/urllib3-2.6.3-py3-none-any.whl", hash = "sha256:bf272323e553dfb2e87d9bfd225ca7b0f467b919d7bbd355436d3fd37cb0acd4", size = 131584, upload-time = "2026-01-07T16:24:42.685Z" },
 ]
 
 [[package]]

libs/checkpoint/langgraph/checkpoint/base/__init__.py

@@ -60,29 +60,20 @@ class CheckpointMetadata(TypedDict, total=False):
     """
     run_id: str
     """The ID of the run that created this checkpoint."""
-    counters_since_delta_snapshot: dict[str, tuple[int, int]]
-    """Per-channel counters since the last `_DeltaSnapshot` was written.
+    delta_updates_since_snapshot: dict[str, int]
+    """Per-channel update count since the last `_DeltaSnapshot` was written.
 
     !!! warning "Beta"
 
         This metadata field backs `DeltaChannel` (beta). The key name and
         contents may change while the delta-channel design stabilizes.
 
-    Maps channel name -> `(updates, supersteps)`:
-
-    - index 0 (`updates`): number of supersteps that wrote to this channel
-      since its last snapshot blob.
-    - index 1 (`supersteps`): total supersteps elapsed since this channel's
-      last snapshot, regardless of whether the channel was written.
-
-    A snapshot fires when EITHER `updates >= ch.snapshot_frequency` OR
-    `supersteps >= DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT` (system-wide bound,
-    default 5000, env `LANGGRAPH_DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT`).
-    The supersteps bound prevents unbounded ancestor walks on threads where
-    a delta channel exists but is no longer being updated.
-
-    Absent on threads that don't use delta channels. Persisted as a
-    2-element list in JSON (no native tuple).
+    Maps channel name → number of supersteps that wrote to this channel
+    since its last snapshot blob. Used by `pregel.create_checkpoint` to
+    decide when to write the next snapshot (when the count reaches the
+    channel's `snapshot_frequency`, snapshot fires and the count resets
+    to 0). Absent on threads that don't use delta channels. Version-format
+    independent — works for int, float, and string version schemes.
     """
 
 
@@ -689,6 +680,123 @@ class BaseCheckpointSaver(Generic[V]):
             result[ch] = entry
         return result
 
+    def get_delta_channel_keepset(
+        self,
+        *,
+        config: RunnableConfig,
+        channels: Sequence[str],
+    ) -> set[str]:
+        """Return ancestor checkpoint_ids that must survive deletion.
+
+        !!! warning "Beta"
+
+            This method is part of the `DeltaChannel` support surface and is
+            in beta. The signature may change while the delta-channel design
+            stabilizes.
+
+        Walks the parent chain from `config` backward, collecting visited
+        checkpoint_ids (inclusive of the target), and terminates per-channel
+        when that channel has a populated `channel_values[ch]` (a
+        `_DeltaSnapshot` blob or a pre-migration plain value). The returned
+        set is the minimum keep-set: every checkpoint_id whose removal would
+        break reconstruction of the listed channels at `config`.
+
+        Pass `channels=[]` to return just `{config.checkpoint_id}` — useful
+        for graphs that don't use `DeltaChannel`.
+
+        Compose this into custom `prune` / `delete_for_runs` / `copy_thread`::
+
+            keep = saver.get_delta_channel_keepset(
+                config=head_config, channels=delta_channels,
+            )
+            delete_rows_not_in(keep)
+
+        Note:
+            The default implementation here uses repeated `get_tuple` calls
+            to walk the parent chain. This is a basic reference implementation
+            suitable for low-frequency maintenance operations (prune, etc.).
+            Custom checkpointer backends may override with a more efficient
+            version tailored to their data model (e.g. a single SQL query
+            with a recursive CTE), but it is not required — the default works
+            correctly for any saver that implements `get_tuple`.
+
+        Args:
+            config: Configuration identifying the target checkpoint.
+            channels: Channel names whose delta history must be preserved.
+                Empty sequence means only the target checkpoint_id is kept.
+
+        Returns:
+            Set of checkpoint_ids that must not be deleted.
+        """
+        target_tuple = self.get_tuple(config)
+        if target_tuple is None:
+            return set()
+        target_id = target_tuple.config["configurable"]["checkpoint_id"]
+        keep: set[str] = {target_id}
+        if not channels:
+            return keep
+        remaining: set[str] = set(channels)
+        for ch in list(remaining):
+            if ch in target_tuple.checkpoint["channel_values"]:
+                remaining.discard(ch)
+        if not remaining:
+            return keep
+        cursor_config: RunnableConfig | None = target_tuple.parent_config
+        while cursor_config is not None and remaining:
+            tup = self.get_tuple(cursor_config)
+            if tup is None:
+                break
+            cid = tup.config["configurable"]["checkpoint_id"]
+            keep.add(cid)
+            for ch in list(remaining):
+                if ch in tup.checkpoint["channel_values"]:
+                    remaining.discard(ch)
+            if not remaining:
+                break
+            cursor_config = tup.parent_config
+        return keep
+
+    async def aget_delta_channel_keepset(
+        self,
+        *,
+        config: RunnableConfig,
+        channels: Sequence[str],
+    ) -> set[str]:
+        """Async version of `get_delta_channel_keepset`.
+
+        !!! warning "Beta"
+
+            This method is part of the `DeltaChannel` support surface and is
+            in beta. See `get_delta_channel_keepset` for full documentation.
+        """
+        target_tuple = await self.aget_tuple(config)
+        if target_tuple is None:
+            return set()
+        target_id = target_tuple.config["configurable"]["checkpoint_id"]
+        keep: set[str] = {target_id}
+        if not channels:
+            return keep
+        remaining: set[str] = set(channels)
+        for ch in list(remaining):
+            if ch in target_tuple.checkpoint["channel_values"]:
+                remaining.discard(ch)
+        if not remaining:
+            return keep
+        cursor_config: RunnableConfig | None = target_tuple.parent_config
+        while cursor_config is not None and remaining:
+            tup = await self.aget_tuple(cursor_config)
+            if tup is None:
+                break
+            cid = tup.config["configurable"]["checkpoint_id"]
+            keep.add(cid)
+            for ch in list(remaining):
+                if ch in tup.checkpoint["channel_values"]:
+                    remaining.discard(ch)
+            if not remaining:
+                break
+            cursor_config = tup.parent_config
+        return keep
+
     def get_next_version(self, current: V | None, channel: None) -> V:
         """Generate the next version ID for a channel.
 

libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py

@@ -44,7 +44,7 @@ if TYPE_CHECKING:
         AllowedMsgpackModules,
     )
 
-LC_REVIVER = Reviver(allowed_objects="core")
+LC_REVIVER = Reviver()
 EMPTY_BYTES = b""
 logger = logging.getLogger(__name__)
 

libs/checkpoint/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "langgraph-checkpoint"
-version = "4.1.0"
+version = "4.1.0a4"
 description = "Library with base interfaces for LangGraph checkpoint savers."
 authors = []
 requires-python = ">=3.10"

libs/checkpoint/tests/test_conformance_delta.py

@@ -25,6 +25,8 @@ async def test_delta_channel_conformance():
         mem_saver,
         capabilities={
             "delta_channel_history",
+            "delta_channel_keepset",
+            "delta_channel_reconstruction",
         },
     )
     for cap, result in report.results.items():

libs/checkpoint/uv.lock

@@ -268,7 +268,7 @@ wheels = [
 
 [[package]]
 name = "langchain-core"
-version = "1.3.3"
+version = "1.3.2"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "jsonpatch" },
@@ -281,9 +281,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "uuid-utils" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/d3/ae/8b74458fc3850ec3d150eb9f45e857db129dafa801fb5cf173dfc9f8bbf3/langchain_core-1.3.3.tar.gz", hash = "sha256:fa510a5db8efdc0c6ff41c0939fb5c00a0183c11f6b84233e892e3227ff69182", size = 915041, upload-time = "2026-05-05T19:02:36.612Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/a8/03/7219502e8ca728d65eb44d7a3eb60239230742a70dbfc9241b9bfd61c4ab/langchain_core-1.3.2.tar.gz", hash = "sha256:fd7a50b2f28ba561fd9d7f5d2760bc9e06cf00cdf820a3ccafe88a94ffa8d5b7", size = 911813, upload-time = "2026-04-24T15:49:23.699Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/1f/01/4771b7ab2af1d1aba5b710bd8f13d9225c609425214b357590a17b01be77/langchain_core-1.3.3-py3-none-any.whl", hash = "sha256:18aae8506f37da7f74398492279a7d6efcee4f8e23c4c41c7af080eeb7ef7bd1", size = 543857, upload-time = "2026-05-05T19:02:34.52Z" },
+    { url = "https://files.pythonhosted.org/packages/7d/d5/8fa4431007cbb7cfed7590f4d6a5dea3ad724f4174d248f6642ef5ce7d05/langchain_core-1.3.2-py3-none-any.whl", hash = "sha256:d44a66127f9f8db735bdfd0ab9661bccb47a97113cfd3f2d89c74864422b7274", size = 542390, upload-time = "2026-04-24T15:49:21.991Z" },
 ]
 
 [[package]]
@@ -300,7 +300,7 @@ wheels = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.1.0"
+version = "4.1.0a4"
 source = { editable = "." }
 dependencies = [
     { name = "langchain-core" },
@@ -1463,11 +1463,11 @@ wheels = [
 
 [[package]]
 name = "urllib3"
-version = "2.7.0"
+version = "2.6.3"
 source = { registry = "https://pypi.org/simple" }
-sdist = { url = "https://files.pythonhosted.org/packages/53/0c/06f8b233b8fd13b9e5ee11424ef85419ba0d8ba0b3138bf360be2ff56953/urllib3-2.7.0.tar.gz", hash = "sha256:231e0ec3b63ceb14667c67be60f2f2c40a518cb38b03af60abc813da26505f4c", size = 433602, upload-time = "2026-05-07T16:13:18.596Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/c7/24/5f1b3bdffd70275f6661c76461e25f024d5a38a46f04aaca912426a2b1d3/urllib3-2.6.3.tar.gz", hash = "sha256:1b62b6884944a57dbe321509ab94fd4d3b307075e0c2eae991ac71ee15ad38ed", size = 435556, upload-time = "2026-01-07T16:24:43.925Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/7f/3e/5db95bcf282c52709639744ca2a8b149baccf648e39c8cc87553df9eae0c/urllib3-2.7.0-py3-none-any.whl", hash = "sha256:9fb4c81ebbb1ce9531cce37674bbc6f1360472bc18ca9a553ede278ef7276897", size = 131087, upload-time = "2026-05-07T16:13:17.151Z" },
+    { url = "https://files.pythonhosted.org/packages/39/08/aaaad47bc4e9dc8c725e68f9d04865dbcb2052843ff09c97b08904852d84/urllib3-2.6.3-py3-none-any.whl", hash = "sha256:bf272323e553dfb2e87d9bfd225ca7b0f467b919d7bbd355436d3fd37cb0acd4", size = 131584, upload-time = "2026-01-07T16:24:42.685Z" },
 ]
 
 [[package]]

libs/cli/langgraph_cli/__init__.py

@@ -1 +1 @@
-__version__ = "0.4.26"
+__version__ = "0.4.25"

libs/cli/langgraph_cli/config.py

@@ -35,12 +35,6 @@ DISALLOWED_BUILD_COMMAND_CHARS = [
 # This blocks background execution (cmd &) while allowing command
 # chaining (cmd1 && cmd2) which is common in build commands.
 _SINGLE_AMPERSAND_RE = re.compile(r"(?<!&)&(?:&&)*(?!&)")
-_API_VERSION_PATTERN = re.compile(
-    r"^(?P<major>\d+)"
-    r"(?:\.(?P<minor>\d+))?"
-    r"(?:\.(?P<patch>\d+))?"
-    r"(?:(?:\.|)(?:[A-Za-z][0-9A-Za-z]*))?$"
-)
 
 
 def has_disallowed_build_command_content(command: str) -> bool:
@@ -129,18 +123,6 @@ def _parse_node_version(version_str: str) -> int:
         ) from None
 
 
-def _parse_api_version_parts(version_str: str) -> tuple[int, ...]:
-    """Parse an API version into numeric components.
-
-    Supports optional prerelease suffixes, e.g. `0.9.0rc1`.
-    """
-    version_core = version_str.split("-", 1)[0]
-    match = _API_VERSION_PATTERN.fullmatch(version_core)
-    if not match:
-        raise ValueError("Version must be major or major.minor or major.minor.patch.")
-    return tuple(int(part) for part in match.groups() if part is not None)
-
-
 def _is_node_graph(spec: str | dict) -> bool:
     """Check if a graph is a Node.js graph based on the file extension."""
     if isinstance(spec, dict):
@@ -194,12 +176,12 @@ def validate_config(config: Config) -> Config:
             )
     if api_version:
         try:
-            parts = _parse_api_version_parts(api_version)
+            parts = tuple(map(int, api_version.split("-")[0].split(".")))
             if len(parts) > 3:
                 raise ValueError(
                     "Version must be major or major.minor or major.minor.patch."
                 )
-        except (TypeError, ValueError):
+        except TypeError:
             raise click.UsageError(
                 f"Invalid version format: {api_version}.\n\n"
                 "Pin to a minor version, e.g.:\n"

libs/cli/tests/unit_tests/test_config.py

@@ -2944,23 +2944,6 @@ def test_docker_tag_with_api_version(in_config: bool):
     assert tag == f"langchain/langgraph-server:{version}-py3.11"
 
 
-@pytest.mark.parametrize("in_config", [False, True])
-@pytest.mark.parametrize("version", ["0.9.0rc1", "0.9.0.dev1"])
-def test_docker_tag_with_prerelease_api_version(version: str, in_config: bool):
-    """Test docker_tag with prerelease and dev api_version values."""
-    config = validate_config(
-        {
-            "python_version": "3.11",
-            "dependencies": ["."],
-            "graphs": {"agent": "./agent.py:graph"},
-            "api_version": version if in_config else None,
-        }
-    )
-
-    tag = docker_tag(config, api_version=version if not in_config else None)
-    assert tag == f"langchain/langgraph-api:{version}-py3.11"
-
-
 def test_config_to_docker_with_api_version():
     """Test config_to_docker function with api_version parameter."""
 

libs/cli/uv-examples/monorepo/pyproject.toml

@@ -5,7 +5,7 @@ description = "uv workspace monorepo example for LangGraph CLI integration test"
 requires-python = ">=3.11"
 dependencies = [
     "langgraph>=0.6.0,<2",
-    "langchain-core>=1.3.3",
+    "langchain-core>=0.2.14",
 ]
 
 [tool.uv.workspace]

libs/cli/uv-examples/monorepo/uv.lock

@@ -21,7 +21,7 @@ dependencies = [
 
 [package.metadata]
 requires-dist = [
-    { name = "langchain-core", specifier = ">=1.3.3" },
+    { name = "langchain-core", specifier = ">=0.2.14" },
     { name = "langgraph", specifier = ">=0.6.0,<2" },
     { name = "shared", editable = "libs/shared" },
 ]
@@ -215,11 +215,10 @@ wheels = [
 
 [[package]]
 name = "langchain-core"
-version = "1.3.3"
+version = "1.2.28"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "jsonpatch" },
-    { name = "langchain-protocol" },
     { name = "langsmith" },
     { name = "packaging" },
     { name = "pydantic" },
@@ -228,21 +227,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "uuid-utils" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/d3/ae/8b74458fc3850ec3d150eb9f45e857db129dafa801fb5cf173dfc9f8bbf3/langchain_core-1.3.3.tar.gz", hash = "sha256:fa510a5db8efdc0c6ff41c0939fb5c00a0183c11f6b84233e892e3227ff69182", size = 915041, upload-time = "2026-05-05T19:02:36.612Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/f8/a4/317a1a3ac1df33a64adb3670bf88bbe3b3d5baa274db6863a979db472897/langchain_core-1.2.28.tar.gz", hash = "sha256:271a3d8bd618f795fdeba112b0753980457fc90537c46a0c11998516a74dc2cb", size = 846119, upload-time = "2026-04-08T18:19:34.867Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/1f/01/4771b7ab2af1d1aba5b710bd8f13d9225c609425214b357590a17b01be77/langchain_core-1.3.3-py3-none-any.whl", hash = "sha256:18aae8506f37da7f74398492279a7d6efcee4f8e23c4c41c7af080eeb7ef7bd1", size = 543857, upload-time = "2026-05-05T19:02:34.52Z" },
-]
-
-[[package]]
-name = "langchain-protocol"
-version = "0.0.15"
-source = { registry = "https://pypi.org/simple" }
-dependencies = [
-    { name = "typing-extensions" },
-]
-sdist = { url = "https://files.pythonhosted.org/packages/4f/24/9777489d6fbbee64af0c8f96d4f840239c408cf694f3394672807dafc490/langchain_protocol-0.0.15.tar.gz", hash = "sha256:9ab2d11ee73944754f10e037e717098d3a6796f0e58afa9cadda6154e7655ade", size = 5862, upload-time = "2026-05-01T22:30:04.748Z" }
-wheels = [
-    { url = "https://files.pythonhosted.org/packages/1d/7a/9c97a7b9cbe4c5dc6a44cdb1545450c28f0c8ce89b9c1f0ee7fbad896263/langchain_protocol-0.0.15-py3-none-any.whl", hash = "sha256:461eb794358f83d5e42635a5797799ffec7b4702314e34edf73ac21e75d3ef79", size = 6982, upload-time = "2026-05-01T22:30:03.877Z" },
+    { url = "https://files.pythonhosted.org/packages/a8/92/32f785f077c7e898da97064f113c73fbd9ad55d1e2169cf3a391b183dedb/langchain_core-1.2.28-py3-none-any.whl", hash = "sha256:80764232581eaf8057bcefa71dbf8adc1f6a28d257ebd8b95ba9b8b452e8c6ac", size = 508727, upload-time = "2026-04-08T18:19:32.823Z" },
 ]
 
 [[package]]
@@ -724,7 +711,7 @@ dependencies = [
 
 [package.metadata]
 requires-dist = [
-    { name = "langchain-core", specifier = ">=1.3.3" },
+    { name = "langchain-core", specifier = ">=0.2.14" },
     { name = "langgraph", specifier = ">=0.6.0,<2" },
 ]
 

libs/cli/uv-examples/simple/pyproject.toml

@@ -5,7 +5,7 @@ description = "Simple single-package uv example for LangGraph CLI integration te
 requires-python = ">=3.11"
 dependencies = [
     "langgraph>=0.6.0,<2",
-    "langchain-core>=1.3.3",
+    "langchain-core>=0.2.14",
 ]
 
 [build-system]

libs/cli/uv-examples/simple/uv.lock

@@ -191,11 +191,10 @@ wheels = [
 
 [[package]]
 name = "langchain-core"
-version = "1.3.3"
+version = "1.2.28"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "jsonpatch" },
-    { name = "langchain-protocol" },
     { name = "langsmith" },
     { name = "packaging" },
     { name = "pydantic" },
@@ -204,21 +203,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "uuid-utils" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/d3/ae/8b74458fc3850ec3d150eb9f45e857db129dafa801fb5cf173dfc9f8bbf3/langchain_core-1.3.3.tar.gz", hash = "sha256:fa510a5db8efdc0c6ff41c0939fb5c00a0183c11f6b84233e892e3227ff69182", size = 915041, upload-time = "2026-05-05T19:02:36.612Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/f8/a4/317a1a3ac1df33a64adb3670bf88bbe3b3d5baa274db6863a979db472897/langchain_core-1.2.28.tar.gz", hash = "sha256:271a3d8bd618f795fdeba112b0753980457fc90537c46a0c11998516a74dc2cb", size = 846119, upload-time = "2026-04-08T18:19:34.867Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/1f/01/4771b7ab2af1d1aba5b710bd8f13d9225c609425214b357590a17b01be77/langchain_core-1.3.3-py3-none-any.whl", hash = "sha256:18aae8506f37da7f74398492279a7d6efcee4f8e23c4c41c7af080eeb7ef7bd1", size = 543857, upload-time = "2026-05-05T19:02:34.52Z" },
-]
-
-[[package]]
-name = "langchain-protocol"
-version = "0.0.15"
-source = { registry = "https://pypi.org/simple" }
-dependencies = [
-    { name = "typing-extensions" },
-]
-sdist = { url = "https://files.pythonhosted.org/packages/4f/24/9777489d6fbbee64af0c8f96d4f840239c408cf694f3394672807dafc490/langchain_protocol-0.0.15.tar.gz", hash = "sha256:9ab2d11ee73944754f10e037e717098d3a6796f0e58afa9cadda6154e7655ade", size = 5862, upload-time = "2026-05-01T22:30:04.748Z" }
-wheels = [
-    { url = "https://files.pythonhosted.org/packages/1d/7a/9c97a7b9cbe4c5dc6a44cdb1545450c28f0c8ce89b9c1f0ee7fbad896263/langchain_protocol-0.0.15-py3-none-any.whl", hash = "sha256:461eb794358f83d5e42635a5797799ffec7b4702314e34edf73ac21e75d3ef79", size = 6982, upload-time = "2026-05-01T22:30:03.877Z" },
+    { url = "https://files.pythonhosted.org/packages/a8/92/32f785f077c7e898da97064f113c73fbd9ad55d1e2169cf3a391b183dedb/langchain_core-1.2.28-py3-none-any.whl", hash = "sha256:80764232581eaf8057bcefa71dbf8adc1f6a28d257ebd8b95ba9b8b452e8c6ac", size = 508727, upload-time = "2026-04-08T18:19:32.823Z" },
 ]
 
 [[package]]
@@ -627,7 +614,7 @@ dependencies = [
 
 [package.metadata]
 requires-dist = [
-    { name = "langchain-core", specifier = ">=1.3.3" },
+    { name = "langchain-core", specifier = ">=0.2.14" },
     { name = "langgraph", specifier = ">=0.6.0,<2" },
 ]
 

libs/cli/uv.lock

@@ -946,11 +946,10 @@ wheels = [
 
 [[package]]
 name = "langchain-core"
-version = "1.3.3"
+version = "1.3.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "jsonpatch", marker = "python_full_version >= '3.11'" },
-    { name = "langchain-protocol", marker = "python_full_version >= '3.11'" },
     { name = "langsmith", marker = "python_full_version >= '3.11'" },
     { name = "packaging", marker = "python_full_version >= '3.11'" },
     { name = "pydantic", marker = "python_full_version >= '3.11'" },
@@ -959,21 +958,9 @@ dependencies = [
     { name = "typing-extensions", marker = "python_full_version >= '3.11'" },
     { name = "uuid-utils", marker = "python_full_version >= '3.11'" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/d3/ae/8b74458fc3850ec3d150eb9f45e857db129dafa801fb5cf173dfc9f8bbf3/langchain_core-1.3.3.tar.gz", hash = "sha256:fa510a5db8efdc0c6ff41c0939fb5c00a0183c11f6b84233e892e3227ff69182", size = 915041, upload-time = "2026-05-05T19:02:36.612Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/92/fe/20190232d9b513242899dbb0c2bb77e31b4d61e343743adbe90ebc2603d2/langchain_core-1.3.0.tar.gz", hash = "sha256:14a39f528bf459aa3aa40d0a7f7f1bae7520d435ef991ae14a4ceb74d8c49046", size = 860755, upload-time = "2026-04-17T14:51:38.298Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/1f/01/4771b7ab2af1d1aba5b710bd8f13d9225c609425214b357590a17b01be77/langchain_core-1.3.3-py3-none-any.whl", hash = "sha256:18aae8506f37da7f74398492279a7d6efcee4f8e23c4c41c7af080eeb7ef7bd1", size = 543857, upload-time = "2026-05-05T19:02:34.52Z" },
-]
-
-[[package]]
-name = "langchain-protocol"
-version = "0.0.15"
-source = { registry = "https://pypi.org/simple" }
-dependencies = [
-    { name = "typing-extensions", marker = "python_full_version >= '3.11'" },
-]
-sdist = { url = "https://files.pythonhosted.org/packages/4f/24/9777489d6fbbee64af0c8f96d4f840239c408cf694f3394672807dafc490/langchain_protocol-0.0.15.tar.gz", hash = "sha256:9ab2d11ee73944754f10e037e717098d3a6796f0e58afa9cadda6154e7655ade", size = 5862, upload-time = "2026-05-01T22:30:04.748Z" }
-wheels = [
-    { url = "https://files.pythonhosted.org/packages/1d/7a/9c97a7b9cbe4c5dc6a44cdb1545450c28f0c8ce89b9c1f0ee7fbad896263/langchain_protocol-0.0.15-py3-none-any.whl", hash = "sha256:461eb794358f83d5e42635a5797799ffec7b4702314e34edf73ac21e75d3ef79", size = 6982, upload-time = "2026-05-01T22:30:03.877Z" },
+    { url = "https://files.pythonhosted.org/packages/f8/e2/dbfa347aa072a6dc4cd38d6f9ebfc730b4c14c258c47f480f4c5c546f177/langchain_core-1.3.0-py3-none-any.whl", hash = "sha256:baf16ee028475df177b9ab8869a751c79406d64a6f12125b93802991b566cced", size = 515140, upload-time = "2026-04-17T14:51:36.274Z" },
 ]
 
 [[package]]
@@ -2320,11 +2307,11 @@ wheels = [
 
 [[package]]
 name = "urllib3"
-version = "2.7.0"
+version = "2.6.3"
 source = { registry = "https://pypi.org/simple" }
-sdist = { url = "https://files.pythonhosted.org/packages/53/0c/06f8b233b8fd13b9e5ee11424ef85419ba0d8ba0b3138bf360be2ff56953/urllib3-2.7.0.tar.gz", hash = "sha256:231e0ec3b63ceb14667c67be60f2f2c40a518cb38b03af60abc813da26505f4c", size = 433602, upload-time = "2026-05-07T16:13:18.596Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/c7/24/5f1b3bdffd70275f6661c76461e25f024d5a38a46f04aaca912426a2b1d3/urllib3-2.6.3.tar.gz", hash = "sha256:1b62b6884944a57dbe321509ab94fd4d3b307075e0c2eae991ac71ee15ad38ed", size = 435556, upload-time = "2026-01-07T16:24:43.925Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/7f/3e/5db95bcf282c52709639744ca2a8b149baccf648e39c8cc87553df9eae0c/urllib3-2.7.0-py3-none-any.whl", hash = "sha256:9fb4c81ebbb1ce9531cce37674bbc6f1360472bc18ca9a553ede278ef7276897", size = 131087, upload-time = "2026-05-07T16:13:17.151Z" },
+    { url = "https://files.pythonhosted.org/packages/39/08/aaaad47bc4e9dc8c725e68f9d04865dbcb2052843ff09c97b08904852d84/urllib3-2.6.3-py3-none-any.whl", hash = "sha256:bf272323e553dfb2e87d9bfd225ca7b0f467b919d7bbd355436d3fd37cb0acd4", size = 131584, upload-time = "2026-01-07T16:24:42.685Z" },
 ]
 
 [[package]]

libs/langgraph/langgraph/_internal/_config.py

@@ -29,9 +29,6 @@ from langgraph._internal._constants import (
 )
 
 DEFAULT_RECURSION_LIMIT = int(getenv("LANGGRAPH_DEFAULT_RECURSION_LIMIT", "10007"))
-DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT = int(
-    getenv("LANGGRAPH_DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT", "5000")
-)
 
 
 def recast_checkpoint_ns(ns: str) -> str:

libs/langgraph/langgraph/channels/delta.py

@@ -32,7 +32,7 @@ class DeltaChannel(Generic[Value], BaseChannel[Any, Any, Any]):
         change in future releases. Threads written with `DeltaChannel` today
         are expected to remain readable, but the surrounding contract
         (`BaseCheckpointSaver.get_delta_channel_history`, the
-        `_DeltaSnapshot` blob shape, the `counters_since_delta_snapshot`
+        `_DeltaSnapshot` blob shape, the `delta_updates_since_snapshot`
         metadata field) is not yet stable.
 
     The reducer receives the current accumulated value and a batch of writes
@@ -47,12 +47,9 @@ class DeltaChannel(Generic[Value], BaseChannel[Any, Any, Any]):
     This lets LangGraph replay checkpointed writes in larger batches than they
     were originally produced without changing reconstructed state.
 
-    Snapshot cadence is driven by two counters: per-channel update count and
-    total supersteps since last snapshot. `create_checkpoint` writes a full
-    `_DeltaSnapshot` blob when EITHER the update count reaches
-    `snapshot_frequency` OR the supersteps count reaches the system-wide
-    `DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT` bound (default 5000), bounding
-    replay depth even for channels that stop receiving writes.
+    Snapshot cadence is driven by per-channel update count. `create_checkpoint`
+    writes a full `_DeltaSnapshot` blob every `snapshot_frequency` updates to
+    this channel, bounding replay depth.
 
     Parameters:
         reducer: `(state, list[writes]) -> new_state`. Must be deterministic

libs/langgraph/langgraph/graph/state.py

@@ -6,7 +6,7 @@ import typing
 import warnings
 from collections import defaultdict
 from collections.abc import Awaitable, Callable, Hashable, Sequence
-from dataclasses import dataclass, is_dataclass
+from dataclasses import is_dataclass
 from datetime import timedelta
 from functools import partial
 from inspect import isclass, isfunction, ismethod, signature
@@ -95,17 +95,6 @@ __all__ = ("StateGraph", "CompiledStateGraph")
 logger = logging.getLogger(__name__)
 
 _CHANNEL_BRANCH_TO = "branch:to:{}"
-_DEFAULT_ERROR_HANDLER_NODE = "__default_error_handler__"
-
-
-@dataclass(slots=True)
-class _NodeDefaults:
-    """Default node policies applied to every node at compile time."""
-
-    retry_policy: RetryPolicy | Sequence[RetryPolicy] | None = None
-    cache_policy: CachePolicy | None = None
-    error_handler: StateNode[Any, Any] | None = None
-    timeout: TimeoutPolicy | None = None
 
 
 def _warn_invalid_state_schema(schema: type[Any] | Any) -> None:
@@ -262,77 +251,10 @@ class StateGraph(Generic[StateT, ContextT, InputT, OutputT]):
         self.output_schema = cast(type[OutputT], output_schema or state_schema)
         self.context_schema = context_schema
 
-        self._node_defaults: _NodeDefaults = _NodeDefaults()
-
         self._add_schema(self.state_schema)
         self._add_schema(self.input_schema, allow_managed=False)
         self._add_schema(self.output_schema, allow_managed=False)
 
-    def set_node_defaults(
-        self,
-        *,
-        retry_policy: RetryPolicy | Sequence[RetryPolicy] | None = None,
-        cache_policy: CachePolicy | None = None,
-        error_handler: StateNode[Any, ContextT] | None = None,
-        timeout: float | timedelta | TimeoutPolicy | None = None,
-    ) -> Self:
-        """Set default node policies that apply to every node in this graph.
-
-        Per-node values passed to `add_node` always take precedence over these
-        defaults. Defaults are applied at `compile()` time. Policies set here
-        are **not** inherited by subgraphs.
-
-        `retry_policy` and `timeout` defaults apply to **all** nodes,
-        including error-handler nodes. `cache_policy` and `error_handler`
-        defaults only apply to regular nodes -- caching error-handler results
-        is unsafe, and handlers must never catch themselves.
-
-        Args:
-            retry_policy: Default retry policy for nodes that don't specify
-                their own via `add_node(..., retry_policy=...)`. Also applies
-                to error-handler nodes.
-            cache_policy: Default cache policy for nodes that don't specify
-                their own via `add_node(..., cache_policy=...)`. Does **not**
-                apply to error-handler nodes.
-            error_handler: Default error handler invoked when any regular node
-                raises and does not have its own `error_handler` set via
-                `add_node`. The handler is **not** invoked when an
-                error-handler node itself raises -- handler failures fail the
-                run.
-            timeout: Default timeout policy for nodes that don't specify their
-                own via `add_node(..., timeout=...)`. Also applies to
-                error-handler nodes. Accepts a `TimeoutPolicy`, a number of
-                seconds (`float`), or a `timedelta`.
-
-        Returns:
-            Self: The builder instance, for chaining.
-
-        Example:
-            ```python
-            graph = (
-                StateGraph(State)
-                .set_node_defaults(
-                    retry_policy=RetryPolicy(max_attempts=3),
-                    error_handler=my_fallback_handler,
-                )
-                .add_node("a", node_a)
-                .add_node("b", node_b, retry_policy=custom_retry)  # overrides default
-                .add_edge(START, "a")
-                .compile()
-            )
-            ```
-        """
-        defaults = self._node_defaults
-        if retry_policy is not None:
-            defaults.retry_policy = retry_policy
-        if cache_policy is not None:
-            defaults.cache_policy = cache_policy
-        if error_handler is not None:
-            defaults.error_handler = error_handler
-        if timeout is not None:
-            defaults.timeout = coerce_timeout_policy(timeout)
-        return self
-
     @property
     def _all_edges(self) -> set[tuple[str, str]]:
         return self.edges | {
@@ -1271,63 +1193,10 @@ class StateGraph(Generic[StateT, ContextT, InputT, OutputT]):
                 key for key, val in self.channels.items() if not is_managed_value(val)
             ]
         )
-        # Apply builder defaults to node specs. Per-node values always win.
-        # Error-handler routing and cache_policy are only assigned to regular
-        # nodes. Retry and timeout defaults also apply to error-handler nodes.
-        defaults = self._node_defaults
-        default_handler_name: str | None = None
-        if defaults.error_handler is not None:
-            if _DEFAULT_ERROR_HANDLER_NODE in self.nodes:
-                raise ValueError(
-                    f"Auto-generated default error handler node "
-                    f"`{_DEFAULT_ERROR_HANDLER_NODE}` already exists."
-                )
-            default_handler_name = _DEFAULT_ERROR_HANDLER_NODE
-            self.nodes[default_handler_name] = StateNodeSpec[Any, ContextT](
-                coerce_to_runnable(
-                    defaults.error_handler,  # type: ignore[arg-type]
-                    name=default_handler_name,
-                    trace=False,
-                ),
-                metadata=None,
-                input_schema=self.state_schema,
-                retry_policy=None,
-                cache_policy=None,
-                is_error_handler=True,
-            )
-
-        # Apply builder defaults to node specs. Per-node values always win.
-        for spec in self.nodes.values():
-            # error_handler: regular nodes only — handlers must never
-            # catch themselves or other handlers.
-            if (
-                not spec.is_error_handler
-                and default_handler_name is not None
-                and spec.error_handler_node is None
-            ):
-                spec.error_handler_node = default_handler_name
-            # retry: all nodes — handlers should be retried on transient
-            # failures just like regular nodes.
-            if defaults.retry_policy is not None and spec.retry_policy is None:
-                spec.retry_policy = defaults.retry_policy
-            # cache: regular nodes only — caching an error-handler result
-            # is unsafe because the input (failed-node state) may differ
-            # across failures even when the cache key matches.
-            if (
-                not spec.is_error_handler
-                and defaults.cache_policy is not None
-                and spec.cache_policy is None
-            ):
-                spec.cache_policy = defaults.cache_policy
-            # timeout: all nodes — a stuck handler should be cancelled the
-            # same way a stuck regular node would be.
-            if defaults.timeout is not None and spec.timeout is None:
-                spec.timeout = defaults.timeout
-
         node_error_handler_map = {
             node_name: spec.error_handler_node
             for node_name, spec in self.nodes.items()
-            if not spec.is_error_handler and spec.error_handler_node is not None
+            if spec.error_handler_node is not None
         }
 
         compiled = CompiledStateGraph[StateT, ContextT, InputT, OutputT](

libs/langgraph/langgraph/pregel/_checkpoint.py

@@ -8,11 +8,11 @@ from langchain_core.runnables import RunnableConfig
 from langgraph.checkpoint.base import (
     BaseCheckpointSaver,
     Checkpoint,
+    CheckpointMetadata,
 )
 from langgraph.checkpoint.base.id import uuid6
 from langgraph.checkpoint.serde.types import _DeltaSnapshot
 
-from langgraph._internal._config import DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT
 from langgraph._internal._typing import MISSING
 from langgraph.channels.base import BaseChannel
 from langgraph.channels.delta import DeltaChannel
@@ -36,26 +36,21 @@ def empty_checkpoint() -> Checkpoint:
 
 def delta_channels_to_snapshot(
     channels: Mapping[str, BaseChannel],
-    counters_since_delta_snapshot: Mapping[str, tuple[int, int]],
+    counts: Mapping[str, int],
 ) -> set[str]:
     """Return the set of DeltaChannel names that should snapshot now.
 
-    A channel snapshots when EITHER its accumulated update count reaches
-    `snapshot_frequency` OR the total supersteps since its last snapshot
-    reaches `DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT`. This is a pure
+    A channel snapshots when its accumulated update count (since the last
+    snapshot) reaches or exceeds `snapshot_frequency`. This is a pure
     predicate — no mutation.
     """
-    result: set[str] = set()
-    for name, ch in channels.items():
-        if not isinstance(ch, DeltaChannel) or not ch.is_available():
-            continue
-        updates, supersteps = counters_since_delta_snapshot.get(name, (0, 0))
-        if (
-            updates >= ch.snapshot_frequency
-            or supersteps >= DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT
-        ):
-            result.add(name)
-    return result
+    return {
+        name
+        for name, ch in channels.items()
+        if isinstance(ch, DeltaChannel)
+        and ch.is_available()
+        and counts.get(name, 0) >= ch.snapshot_frequency
+    }
 
 
 def create_checkpoint(
@@ -74,7 +69,7 @@ def create_checkpoint(
     is written into `channel_values[k]`. Other delta channels are omitted
     from `channel_values` — the ancestor walk reconstructs their state
     from `checkpoint_writes`. Callers compute the set via
-    `delta_channels_to_snapshot(channels, counters)`; defaults to empty
+    `delta_channels_to_snapshot(channels, counts)`; defaults to empty
     (no snapshots) when not provided.
     """
     ts = datetime.now(timezone.utc).isoformat()
@@ -236,3 +231,17 @@ def copy_checkpoint(checkpoint: Checkpoint) -> Checkpoint:
         versions_seen={k: v.copy() for k, v in checkpoint["versions_seen"].items()},
         updated_channels=checkpoint.get("updated_channels", None),
     )
+
+
+def read_delta_updates_since_snapshot(
+    metadata: CheckpointMetadata | None,
+) -> dict[str, int]:
+    """Read the per-channel update counter from checkpoint metadata.
+
+    Returns an empty dict for missing/None metadata; the dict is
+    `total=False` on `CheckpointMetadata`, so absence means "no prior
+    delta-channel activity tracked."
+    """
+    if not metadata:
+        return {}
+    return dict(metadata.get("delta_updates_since_snapshot", {}) or {})

libs/langgraph/langgraph/pregel/_loop.py

@@ -203,12 +203,6 @@ class PregelLoop:
     # `__enter__`; stays `None` only when no checkpointer.
     _delta_write_futs: list[Any] | None = None
 
-    # Same pattern as `_delta_write_futs` but for error-handler writes.
-    # When `put_writes` persists an ERROR_SOURCE_NODE marker, the future is
-    # appended here.  `schedule_error_handler` / `aschedule_error_handler`
-    # drain this list so the write is durable before the handler starts.
-    _error_handler_write_futs: list[Any] | None = None
-
     # Exit-mode accumulator: every delta-channel write produced during this
     # run (input writes from `_first` + per-superstep writes captured in
     # `after_tick`). At exit, `_put_exit_delta_writes` filters out channels
@@ -480,13 +474,6 @@ class PregelLoop:
                 isinstance(self.specs.get(c), DeltaChannel) for c, _ in writes_to_save
             ):
                 self._delta_write_futs.append(fut)
-            # ERROR_SOURCE_NODE is only appended by commit() when the task
-            # has an error handler (_should_route_to_error_handler), so this
-            # check naturally limits future collection to those tasks.
-            if self._error_handler_write_futs is not None and any(
-                c == ERROR_SOURCE_NODE for c, _ in writes
-            ):
-                self._error_handler_write_futs.append(fut)
         # output writes
         if hasattr(self, "tasks"):
             self.output_writes(task_id, writes)
@@ -566,7 +553,7 @@ class PregelLoop:
             self.tasks[pushed.id] = pushed
             # match any pending writes to the new task
             if not self.is_replaying:
-                self._reapply_writes_to_succeeded_nodes({pushed.id: pushed})
+                self._match_writes({pushed.id: pushed})
             # return the new task, to be started if not run before
             return pushed
 
@@ -644,8 +631,7 @@ class PregelLoop:
 
         # if there are pending writes from a previous loop, apply them
         if not self.is_replaying and self.checkpoint_pending_writes:
-            self._reapply_writes_to_succeeded_nodes(self.tasks)
-            self._resume_error_handlers_if_applicable()
+            self._match_writes(self.tasks)
 
         # before execution, check if we should interrupt
         if self.interrupt_before and should_interrupt(
@@ -712,88 +698,13 @@ class PregelLoop:
 
     # private
 
-    def _reapply_writes_to_succeeded_nodes(
-        self, tasks: Mapping[str, PregelExecutableTask]
-    ) -> None:
-        """Restore successful channel writes from checkpoint to in-memory tasks.
-
-        Skips control signals (ERROR, ERROR_SOURCE_NODE, INTERRUPT, RESUME)
-        so that failed/interrupted tasks remain with empty writes and will be
-        re-executed (or routed to error handlers) by the runner.
-        """
+    def _match_writes(self, tasks: Mapping[str, PregelExecutableTask]) -> None:
         for tid, k, v in self.checkpoint_pending_writes:
             if k in (ERROR, ERROR_SOURCE_NODE, INTERRUPT, RESUME):
                 continue
             if task := tasks.get(tid):
                 task.writes.append((k, v))
 
-    def _resume_error_handlers_if_applicable(self) -> None:
-        """On resume, schedule error handlers for tasks that failed in a prior run.
-
-        Called right after ``_reapply_writes_to_succeeded_nodes`` during ``tick()``.
-        At that point, ``_reapply_writes_to_succeeded_nodes`` has already skipped
-        ERROR / ERROR_SOURCE_NODE writes, so a previously-failed task still has
-        empty ``writes``.  Without intervention the runner (which executes only
-        tasks where ``not t.writes``) would re-run the original node.
-
-        This method prevents that re-execution for nodes that have an error
-        handler:
-
-        1. Scan ``checkpoint_pending_writes`` for ERROR_SOURCE_NODE markers
-           persisted by a prior ``commit()``.  Each marker means "this task
-           already failed and was routed to an error handler".
-        2. For each such task, write ``(ERROR, error)`` into ``task.writes``
-           so the task is no longer empty — the runner will skip it.
-        3. Prepare a fresh error-handler task and add it to ``self.tasks``.
-           Because the handler task starts with empty ``writes``, the runner
-           will pick it up and execute it.
-        """
-        # Phase 1: collect task-ids that have ERROR_SOURCE_NODE + ERROR pairs.
-        failed: dict[str, BaseException] = {}
-        for tid, chan, val in self.checkpoint_pending_writes:
-            if chan == ERROR_SOURCE_NODE:
-                error = next(
-                    (
-                        v
-                        for t, c, v in self.checkpoint_pending_writes
-                        if t == tid and c == ERROR
-                    ),
-                    None,
-                )
-                if error is not None:
-                    failed[tid] = error
-        # Phase 2: mark originals as done, schedule handler tasks.
-        for task_id, error in failed.items():
-            task = self.tasks.get(task_id)
-            if task is None:
-                continue
-            handler_node = self.nodes[task.name].error_handler_node
-            if not handler_node:
-                continue
-            # Non-empty writes → runner's `not t.writes` filter skips this task.
-            task.writes.append((ERROR, error))
-            # The handler task starts with empty writes → runner will execute it.
-            handler_task = prepare_node_error_handler_task(
-                task,
-                handler_node_name=handler_node,
-                failed_error=error,
-                checkpoint=self.checkpoint,
-                pending_writes=self.checkpoint_pending_writes,
-                processes=self.nodes,
-                channels=self.channels,
-                managed=self.managed,
-                config=task.config,
-                step=self.step,
-                stop=self.stop,
-                store=self.store,
-                checkpointer=self.checkpointer,
-                manager=self.manager,
-                retry_policy=self.retry_policy,
-                cache_policy=self.cache_policy,
-            )
-            if handler_task is not None:
-                self.tasks[handler_task.id] = handler_task
-
     def _pending_interrupts(self) -> set[str]:
         """Return the set of interrupt ids that are pending without corresponding resume values."""
         # mapping of task ids to interrupt ids
@@ -1067,41 +978,35 @@ class PregelLoop:
         if exiting and self.checkpoint["id"] == self.checkpoint_id_saved:
             # checkpoint already saved
             return
-        # Per-delta-channel counter bookkeeping.
-        #
-        # Each delta channel tracks a (updates, supersteps) tuple:
-        # - `updates` increments only when the channel is written this step.
-        # - `supersteps` increments every superstep regardless.
+        # Per-delta-channel update bookkeeping.
         #
         # `_put_checkpoint` is called once per superstep with a fresh
         # metadata dict (source="input"|"loop"|"fork") — those are the
-        # intermediate calls that bump counters. In exit mode,
+        # intermediate calls that bump the count by +1 for each delta
+        # channel touched that step. In exit mode,
         # `_suppress_interrupt`(will rename to _on_loop_exit soon)
         # additionally calls `_put_checkpoint(self.checkpoint_metadata)` AT
         # EXIT to commit the final checkpoint — this runs *after* the last
         # intermediate call already counted the last superstep. So the
         # exit call must NOT bump again or it would double-count the last
-        # superstep.
+        # superstep. (Sync/async durability does not call `_put_checkpoint`
+        # at exit, so the issue only surfaces in exit mode. force_delta_snapshot
+        # used to mask this latent bug by resetting every count to 0.)
         if not exiting:
-            prev_counters = dict(
-                self.checkpoint_metadata.get("counters_since_delta_snapshot") or {}
+            prev_counts = dict(
+                self.checkpoint_metadata.get("delta_updates_since_snapshot", {}) or {}
             )
-            new_counters: dict[str, tuple[int, int]] = {}
-            updated = self.updated_channels or set()
-            for ch_name, ch in self.channels.items():
-                if not isinstance(ch, DeltaChannel):
-                    continue
-                u, s = prev_counters.get(ch_name, (0, 0))
-                s += 1
-                if ch_name in updated:
-                    u += 1
-                new_counters[ch_name] = (u, s)
+            new_counts = dict(prev_counts)
+            if self.updated_channels:
+                for ch_name in self.updated_channels:
+                    if isinstance(self.channels.get(ch_name), DeltaChannel):
+                        new_counts[ch_name] = new_counts.get(ch_name, 0) + 1
             metadata["step"] = self.step
             metadata["parents"] = self.config[CONF].get(CONFIG_KEY_CHECKPOINT_MAP, {})
             self.checkpoint_metadata = metadata
         else:
-            new_counters = dict(
-                self.checkpoint_metadata.get("counters_since_delta_snapshot") or {}
+            new_counts = dict(
+                self.checkpoint_metadata.get("delta_updates_since_snapshot", {}) or {}
             )
         # do checkpoint?
         do_checkpoint = self._checkpointer_put_after_previous is not None and (
@@ -1109,7 +1014,7 @@ class PregelLoop:
         )
         # create new checkpoint
         channels_to_snapshot = (
-            delta_channels_to_snapshot(self.channels, new_counters)
+            delta_channels_to_snapshot(self.channels, new_counts)
             if do_checkpoint
             else set()
         )
@@ -1125,12 +1030,11 @@ class PregelLoop:
             channels_to_snapshot=channels_to_snapshot,
         )
         for k in channels_to_snapshot:
-            new_counters[k] = (0, 0)
-        non_zero = {k: v for k, v in new_counters.items() if v != (0, 0)}
-        if non_zero:
-            self.checkpoint_metadata["counters_since_delta_snapshot"] = non_zero
-        elif "counters_since_delta_snapshot" in self.checkpoint_metadata:
-            del self.checkpoint_metadata["counters_since_delta_snapshot"]
+            new_counts[k] = 0
+        if new_counts:
+            self.checkpoint_metadata["delta_updates_since_snapshot"] = new_counts
+        elif "delta_updates_since_snapshot" in self.checkpoint_metadata:
+            del self.checkpoint_metadata["delta_updates_since_snapshot"]
         # sanitize TASK channel in the checkpoint before saving (durability=="exit")
         if TASKS in self.checkpoint["channel_values"] and any(
             isinstance(channel, UntrackedValue) for channel in self.channels.values()
@@ -1205,10 +1109,8 @@ class PregelLoop:
         ):
             return
 
-        counters = dict(
-            self.checkpoint_metadata.get("counters_since_delta_snapshot") or {}
-        )
-        channels_to_snapshot = delta_channels_to_snapshot(self.channels, counters)
+        counts = self.checkpoint_metadata.get("delta_updates_since_snapshot", {}) or {}
+        channels_to_snapshot = delta_channels_to_snapshot(self.channels, counts)
 
         pending = [
             (step, tid, ch, v)
@@ -1543,10 +1445,12 @@ class SyncPregelLoop(PregelLoop, AbstractContextManager):
         handler_node = self.nodes[failed_task.name].error_handler_node
         if not handler_node:
             return None
-        # ensure error + ERROR_SOURCE_NODE writes are durable before handler runs
-        if self._error_handler_write_futs:
-            futs, self._error_handler_write_futs = self._error_handler_write_futs, []
-            concurrent.futures.wait(futs)
+        writes = list(failed_task.writes)
+        writes.append((ERROR_SOURCE_NODE, failed_task.name))
+        self.put_writes(
+            failed_task.id,
+            writes,
+        )
         handler_task = prepare_node_error_handler_task(
             failed_task,
             handler_node_name=handler_node,
@@ -1569,7 +1473,7 @@ class SyncPregelLoop(PregelLoop, AbstractContextManager):
             return None
         self.tasks[handler_task.id] = handler_task
         if not self.is_replaying:
-            self._reapply_writes_to_succeeded_nodes({handler_task.id: handler_task})
+            self._match_writes({handler_task.id: handler_task})
         for task in self.match_cached_writes():
             self.output_writes(task.id, task.writes, cached=True)
         return handler_task
@@ -1651,7 +1555,6 @@ class SyncPregelLoop(PregelLoop, AbstractContextManager):
             else []
         )
         self._delta_write_futs = []
-        self._error_handler_write_futs = []
         self._exit_delta_writes = (
             [] if self.durability == "exit" and self.checkpointer is not None else None
         )
@@ -1797,10 +1700,12 @@ class AsyncPregelLoop(PregelLoop, AbstractAsyncContextManager):
         handler_node = self.nodes[failed_task.name].error_handler_node
         if not handler_node:
             return None
-        # ensure error + ERROR_SOURCE_NODE writes are durable before handler runs
-        if self._error_handler_write_futs:
-            futs, self._error_handler_write_futs = self._error_handler_write_futs, []
-            await asyncio.gather(*futs)
+        writes = list(failed_task.writes)
+        writes.append((ERROR_SOURCE_NODE, failed_task.name))
+        self.put_writes(
+            failed_task.id,
+            writes,
+        )
         handler_task = prepare_node_error_handler_task(
             failed_task,
             handler_node_name=handler_node,
@@ -1823,7 +1728,7 @@ class AsyncPregelLoop(PregelLoop, AbstractAsyncContextManager):
             return None
         self.tasks[handler_task.id] = handler_task
         if not self.is_replaying:
-            self._reapply_writes_to_succeeded_nodes({handler_task.id: handler_task})
+            self._match_writes({handler_task.id: handler_task})
         for task in await self.amatch_cached_writes():
             self.output_writes(task.id, task.writes, cached=True)
         return handler_task
@@ -1908,7 +1813,6 @@ class AsyncPregelLoop(PregelLoop, AbstractAsyncContextManager):
             else []
         )
         self._delta_write_futs = []
-        self._error_handler_write_futs = []
         self._exit_delta_writes = (
             [] if self.durability == "exit" and self.checkpointer is not None else None
         )

libs/langgraph/langgraph/pregel/_runner.py

@@ -31,7 +31,6 @@ from langgraph._internal._constants import (
     CONFIG_KEY_CALL,
     CONFIG_KEY_SCRATCHPAD,
     ERROR,
-    ERROR_SOURCE_NODE,
     INTERRUPT,
     NO_WRITES,
     RESUME,
@@ -598,7 +597,7 @@ class PregelRunner:
                 if self._should_route_to_error_handler(task) and not isinstance(
                     exception, GraphBubbleUp
                 ):
-                    task.writes.append((ERROR_SOURCE_NODE, task.name))
+                    # Mark early in commit path; loop-side routing may happen later.
                     self._handled_exception_ids.add(id(exception))
                 self.put_writes()(task.id, task.writes)  # type: ignore[misc]
         else:

libs/langgraph/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "langgraph"
-version = "1.2.0"
+version = "1.2.0a7"
 description = "Building stateful, multi-actor applications with LLMs"
 authors = []
 requires-python = ">=3.10"
@@ -24,10 +24,10 @@ classifiers = [
     'Programming Language :: Python :: 3.13',
 ]
 dependencies = [
-    "langchain-core>=1.4.0,<2",
-    "langgraph-checkpoint>=4.1.0,<5.0.0",
+    "langchain-core>=1.4.0a2,<2",
+    "langgraph-checkpoint>=4.1.0a4,<5.0.0",
     "langgraph-sdk>=0.3.0,<0.4.0",
-    "langgraph-prebuilt>=1.1.0,<1.2.0",
+    "langgraph-prebuilt>=1.1.0a2,<1.2.0",
     "xxhash>=3.5.0",
     "pydantic>=2.7.4",
 ]

libs/langgraph/tests/test_delta_channel_exit_mode.py

@@ -160,8 +160,8 @@ async def test_exit_resumed_run_sub_freq() -> None:
 
 
 async def test_exit_count_parity_sync_vs_exit() -> None:
-    """Sync and exit durability produce the same update count in
-    counters_since_delta_snapshot after an equivalent run."""
+    """Sync and exit durability produce the same delta_updates_since_snapshot
+    after an equivalent run."""
     for durability in ("sync", "exit"):
         saver = InMemorySaver()
         graph = _build_graph(saver)
@@ -175,13 +175,9 @@ async def test_exit_count_parity_sync_vs_exit() -> None:
 
         head = saver.get_tuple(config)
         assert head is not None
-        counters = head.metadata.get("counters_since_delta_snapshot", {})
-        updates, supersteps = counters.get("messages", (0, 0))
-        assert updates == 2, (
-            f"durability={durability}: expected updates=2, got {updates}"
-        )
-        assert supersteps >= 2, (
-            f"durability={durability}: expected supersteps>=2, got {supersteps}"
+        counts = head.metadata.get("delta_updates_since_snapshot", {})
+        assert counts.get("messages") == 2, (
+            f"durability={durability}: expected count=2, got {counts}"
         )
 
 
@@ -200,9 +196,8 @@ async def test_exit_snapshot_fires_at_frequency() -> None:
     )
     head = saver.get_tuple(config)
     assert head is not None
-    counters1 = head.metadata.get("counters_since_delta_snapshot", {})
-    updates1 = counters1.get("messages", (0, 0))[0]
-    assert updates1 == 2
+    count1 = head.metadata.get("delta_updates_since_snapshot", {}).get("messages", 0)
+    assert count1 == 2
 
     graph.invoke(
         {"messages": [HumanMessage(content="m2", id="h2")]},
@@ -211,9 +206,8 @@ async def test_exit_snapshot_fires_at_frequency() -> None:
     )
     head = saver.get_tuple(config)
     assert head is not None
-    counters2 = head.metadata.get("counters_since_delta_snapshot", {})
-    updates2 = counters2.get("messages", (0, 0))[0]
-    assert updates2 == 0, f"Expected reset to 0 after snapshot, got {updates2}"
+    count2 = head.metadata.get("delta_updates_since_snapshot", {}).get("messages", 0)
+    assert count2 == 0, f"Expected reset to 0 after snapshot, got {count2}"
     assert isinstance(head.checkpoint["channel_values"].get("messages"), _DeltaSnapshot)
 
 
@@ -290,7 +284,7 @@ async def test_exit_multi_run_replay_chain() -> None:
 
 async def test_exit_metadata_round_trip() -> None:
     """K=5 consecutive exit runs with snapshot_frequency=5. Verify metadata
-    counters_since_delta_snapshot increments correctly across runs."""
+    delta_updates_since_snapshot increments correctly across runs."""
     freq = 5
     saver = InMemorySaver()
     graph = _build_graph(saver, freq=freq)
@@ -304,16 +298,15 @@ async def test_exit_metadata_round_trip() -> None:
         )
         head = saver.get_tuple(config)
         assert head is not None
-        counters = head.metadata.get("counters_since_delta_snapshot", {})
-        updates = counters.get("messages", (0, 0))[0]
+        count = head.metadata.get("delta_updates_since_snapshot", {}).get("messages", 0)
         cumulative = i * 2
         if cumulative >= freq:
-            assert updates == 0 or updates == cumulative % freq or updates < freq, (
-                f"After run {i}: updates={updates} should have reset or be partial"
+            assert count == 0 or count == cumulative % freq or count < freq, (
+                f"After run {i}: count={count} should have reset or be partial"
             )
         else:
-            assert updates == cumulative, (
-                f"After run {i}: expected {cumulative}, got {updates}"
+            assert count == cumulative, (
+                f"After run {i}: expected {cumulative}, got {count}"
             )
 
 

libs/langgraph/tests/test_delta_channel_supersteps_bound.py

@@ -1,195 +0,0 @@
-"""Tests for the supersteps-since-last-snapshot bound on DeltaChannel.
-
-Validates that a delta channel which stops receiving writes is still
-force-snapshotted after DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT supersteps,
-preventing unbounded ancestor walks.
-"""
-
-from typing import Annotated, Any
-from unittest.mock import patch
-
-import pytest
-from langgraph.checkpoint.memory import InMemorySaver
-from langgraph.checkpoint.serde.types import _DeltaSnapshot
-from typing_extensions import TypedDict
-
-from langgraph.channels.delta import DeltaChannel
-from langgraph.graph import END, START, StateGraph
-from langgraph.pregel._checkpoint import delta_channels_to_snapshot
-
-pytestmark = pytest.mark.anyio
-
-
-def _simple_reducer(current: list, updates: list) -> list:
-    """Flatten updates into current list (each update is itself a list)."""
-    result = list(current)
-    for u in updates:
-        if isinstance(u, list):
-            result.extend(u)
-        else:
-            result.append(u)
-    return result
-
-
-def _build_two_channel_graph(
-    checkpointer: InMemorySaver,
-    *,
-    freq_a: int = 10_000,
-    freq_b: int = 10_000,
-    n_loops: int = 1,
-) -> Any:
-    """Graph with two delta channels A and B.
-
-    The node only writes to channel A; B is never written by the node.
-    `n_loops` controls how many supersteps the graph runs (via chained nodes).
-    """
-    ch_a = DeltaChannel(_simple_reducer, list, snapshot_frequency=freq_a)
-    ch_b = DeltaChannel(_simple_reducer, list, snapshot_frequency=freq_b)
-    State = TypedDict(  # noqa: UP013
-        "State",
-        {"a": Annotated[list, ch_a], "b": Annotated[list, ch_b]},
-    )  # type: ignore[call-overload]
-
-    builder = StateGraph(State)
-
-    for i in range(n_loops):
-        name = f"step_{i}"
-
-        def node_fn(state: dict, _i: int = i) -> dict:
-            return {"a": [f"a-val-{_i}"]}
-
-        builder.add_node(name, node_fn)
-        if i == 0:
-            builder.add_edge(START, name)
-        else:
-            builder.add_edge(f"step_{i - 1}", name)
-        if i == n_loops - 1:
-            builder.add_edge(name, END)
-
-    return builder.compile(checkpointer=checkpointer)
-
-
-async def test_forced_snapshot_single_run() -> None:
-    """A single invoke with enough supersteps triggers snapshot on the
-    unwritten channel B via the supersteps bound."""
-    max_ss = 3
-    with patch(
-        "langgraph.pregel._checkpoint.DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT",
-        max_ss,
-    ):
-        saver = InMemorySaver()
-        graph = _build_two_channel_graph(saver, n_loops=4)
-        config = {"configurable": {"thread_id": "single-run-ss"}}
-
-        graph.invoke({"a": ["seed-a"], "b": ["seed-b"]}, config)
-
-        head = saver.get_tuple(config)
-        assert head is not None
-        assert isinstance(head.checkpoint["channel_values"].get("b"), _DeltaSnapshot), (
-            "Channel B should have been force-snapshotted via supersteps bound"
-        )
-
-        state = graph.get_state(config)
-        assert state.values["b"] == ["seed-b"]
-        assert "seed-a" in state.values["a"]
-
-
-async def test_forced_snapshot_accumulates_across_runs() -> None:
-    """Supersteps counter for an unwritten channel persists across separate
-    invoke() calls. After enough runs, the channel is force-snapshotted."""
-    max_ss = 5
-    with patch(
-        "langgraph.pregel._checkpoint.DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT",
-        max_ss,
-    ):
-        saver = InMemorySaver()
-        graph = _build_two_channel_graph(saver, n_loops=1)
-        config = {"configurable": {"thread_id": "multi-run-ss"}}
-
-        graph.invoke({"a": ["init-a"], "b": ["init-b"]}, config)
-
-        for i in range(1, 6):
-            graph.invoke({"a": [f"run-{i}"]}, config)
-
-            head = saver.get_tuple(config)
-            assert head is not None
-            counters = head.metadata.get("counters_since_delta_snapshot", {})
-            b_counters = counters.get("b", (0, 0))
-
-            if b_counters == (0, 0):
-                assert isinstance(
-                    head.checkpoint["channel_values"].get("b"), _DeltaSnapshot
-                ), f"Run {i}: counter reset but no snapshot blob for B"
-                break
-        else:
-            pytest.fail("Channel B was never force-snapshotted after multiple runs")
-
-        state = graph.get_state(config)
-        assert state.values["b"] == ["init-b"]
-        assert "init-a" in state.values["a"]
-
-
-async def test_predicate_fires_on_supersteps_overflow() -> None:
-    """Unit test: delta_channels_to_snapshot fires when supersteps >= MAX
-    even when updates == 0."""
-    ch = DeltaChannel(_simple_reducer, list, snapshot_frequency=10_000)
-    ch.key = "x"
-    ch_instance = ch.from_checkpoint(None)
-
-    channels = {"x": ch_instance}
-    counters: dict[str, tuple[int, int]] = {"x": (0, 5000)}
-
-    result = delta_channels_to_snapshot(channels, counters)
-    assert "x" in result
-
-    counters_below: dict[str, tuple[int, int]] = {"x": (0, 4999)}
-    result2 = delta_channels_to_snapshot(channels, counters_below)
-    assert "x" not in result2
-
-
-async def test_counter_reset_after_supersteps_snapshot() -> None:
-    """After the supersteps bound triggers a snapshot, the counters for
-    that channel reset. Verify by using a bound higher than one run's
-    supersteps so we can see the counter in an intermediate state."""
-    max_ss = 15
-    with patch(
-        "langgraph.pregel._checkpoint.DELTA_MAX_SUPERSTEPS_SINCE_SNAPSHOT",
-        max_ss,
-    ):
-        saver = InMemorySaver()
-        graph = _build_two_channel_graph(saver, n_loops=4)
-        config = {"configurable": {"thread_id": "counter-reset"}}
-
-        graph.invoke({"a": ["seed-a"], "b": ["seed-b"]}, config)
-
-        head = saver.get_tuple(config)
-        assert head is not None
-        counters = head.metadata.get("counters_since_delta_snapshot", {})
-        b_counters = counters.get("b", (0, 0))
-        run1_supersteps = b_counters[1]
-        assert run1_supersteps > 0, "Should have some supersteps"
-        assert b_counters[0] == 1, "B written once (input step)"
-
-        graph.invoke({"a": ["more-a"]}, config)
-        head2 = saver.get_tuple(config)
-        assert head2 is not None
-        counters2 = head2.metadata.get("counters_since_delta_snapshot", {})
-        b_counters2 = counters2.get("b", (0, 0))
-        run2_supersteps = b_counters2[1]
-        assert run2_supersteps > run1_supersteps, "Supersteps should accumulate"
-        assert b_counters2[0] == 1, "B written once total (only original input)"
-
-        graph.invoke({"a": ["even-more"]}, config)
-        head3 = saver.get_tuple(config)
-        assert head3 is not None
-        assert isinstance(
-            head3.checkpoint["channel_values"].get("b"), _DeltaSnapshot
-        ), "B should have snapshotted at supersteps >= max_ss"
-        counters3 = head3.metadata.get("counters_since_delta_snapshot", {})
-        b_counters3 = counters3.get("b", (0, 0))
-        assert b_counters3[1] < max_ss, (
-            f"After snapshot, supersteps should have reset, got {b_counters3}"
-        )
-
-        state = graph.get_state(config)
-        assert state.values["b"] == ["seed-b"]

libs/langgraph/tests/test_retry.py

@@ -15,7 +15,7 @@ from langchain_core.callbacks import AsyncCallbackManagerForLLMRun, BaseCallback
 from langchain_core.language_models.fake_chat_models import GenericFakeChatModel
 from langchain_core.messages import AIMessage, AIMessageChunk, BaseMessage, HumanMessage
 from langchain_core.outputs import ChatGeneration, ChatGenerationChunk, ChatResult
-from langchain_core.runnables import RunnableConfig, RunnableLambda, RunnableParallel
+from langchain_core.runnables import RunnableLambda, RunnableParallel
 from langgraph.checkpoint.memory import InMemorySaver, MemorySaver
 from langgraph.checkpoint.serde.jsonplus import JsonPlusSerializer
 from typing_extensions import TypedDict
@@ -1674,28 +1674,15 @@ async def test_arun_with_retry_timeout_observer_tracks_attempts():
 async def test_arun_with_retry_timeout_observer_emits_progress_on_heartbeat():
     events: list = []
 
-    # `_TimedAttemptScope.__init__` sets `_last_progress` to `time.monotonic()`,
-    # but the watchdog itself doesn't start running until after `wrap_config`
-    # and task scheduling — under CI load that gap can be large enough to eat
-    # the entire idle window before the task body's first await even runs. We
-    # defend against that by:
-    #   1. Using a generous idle_timeout so scheduling slack stays well within it.
-    #   2. Calling `runtime.heartbeat()` BEFORE the first sleep, which resets
-    #      `_last_progress` to "now" the moment the task body actually starts.
-    idle_timeout_s = 1.0
-
     class HeartbeatProc:
         async def ainvoke(self, input, config):
             runtime = config[CONF][CONFIG_KEY_RUNTIME]
-            runtime.heartbeat()  # reset the idle clock at task-body entry
             for _ in range(8):
                 await asyncio.sleep(0.05)
                 runtime.heartbeat()
             return "ok"
 
-    task = _make_task(
-        HeartbeatProc(), timeout=_idle_timeout(idle_timeout_s), name="heartbeat"
-    )
+    task = _make_task(HeartbeatProc(), timeout=_idle_timeout(0.2), name="heartbeat")
     task.config[CONF][CONFIG_KEY_TIMED_ATTEMPT_OBSERVER] = events.append
     assert await arun_with_retry(task, retry_policy=None) == "ok"
 
@@ -1704,13 +1691,13 @@ async def test_arun_with_retry_timeout_observer_emits_progress_on_heartbeat():
     assert by_event[-1] == "finish"
     progress = [ev for ev in events if ev.event == "progress"]
     assert progress, "expected at least one progress event from heartbeat"
-    # Rate limit is `idle_timeout / 4` = 0.25s; with the task running for
-    # ~400ms we expect 1–2 progress events (well below the 9 heartbeats).
+    # Rate limit is `idle_timeout / 4` = 0.05s; with 8 heartbeats spaced ~0.05s
+    # we should see at most ~one progress event per heartbeat (well below 8).
     assert len(progress) <= len(by_event)
     for ev in progress:
         assert ev.context.task_name == "heartbeat"
         assert ev.context.attempt == 1
-        assert ev.context.idle_timeout_secs == idle_timeout_s
+        assert ev.context.idle_timeout_secs == 0.2
         assert isinstance(ev.progress_at, datetime)
 
 
@@ -2280,525 +2267,3 @@ def test_node_without_error_handler_still_fails_run():
 
     with pytest.raises(ValueError, match="no handler"):
         graph.invoke({"foo": ""})
-
-
-# ---------------------------------------------------------------------------
-# set_node_defaults()
-# ---------------------------------------------------------------------------
-
-
-def test_set_node_defaults_error_handler_catches_all_nodes():
-    class State(TypedDict):
-        route: str
-        foo: Annotated[list[str], operator.add]
-
-    def route_node(state: State) -> Command:
-        return Command(goto=state["route"])
-
-    def fail_a(state: State) -> State:
-        raise RuntimeError("a failed")
-
-    def fail_b(state: State) -> State:
-        raise RuntimeError("b failed")
-
-    captured: dict[str, list[str]] = {"nodes": []}
-
-    def default_handler(state: State, error: NodeError) -> State:
-        captured["nodes"].append(error.node)
-        return {"foo": [f"handled_{error.node}"]}
-
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(error_handler=default_handler)
-        .add_node("route_node", route_node)
-        .add_node("fail_a", fail_a)
-        .add_node("fail_b", fail_b)
-        .add_edge(START, "route_node")
-        .add_conditional_edges(
-            "route_node", lambda s: s["route"], path_map=["fail_a", "fail_b"]
-        )
-        .compile()
-    )
-
-    result_a = graph.invoke({"route": "fail_a", "foo": []})
-    result_b = graph.invoke({"route": "fail_b", "foo": []})
-    assert result_a["foo"] == ["handled_fail_a"]
-    assert result_b["foo"] == ["handled_fail_b"]
-    assert "fail_a" in captured["nodes"]
-    assert "fail_b" in captured["nodes"]
-
-
-def test_set_node_defaults_error_handler_overridden_by_node_handler():
-    class State(TypedDict):
-        route: str
-        foo: Annotated[list[str], operator.add]
-
-    def route_node(state: State) -> Command:
-        return Command(goto=state["route"])
-
-    def fail_a(state: State) -> State:
-        raise RuntimeError("a failed")
-
-    def fail_b(state: State) -> State:
-        raise RuntimeError("b failed")
-
-    captured: dict[str, list[str]] = {"handler": []}
-
-    def node_handler(state: State, error: NodeError) -> State:
-        captured["handler"].append(f"node:{error.node}")
-        return {"foo": [f"node_handled_{error.node}"]}
-
-    def default_handler(state: State, error: NodeError) -> State:
-        captured["handler"].append(f"default:{error.node}")
-        return {"foo": [f"default_handled_{error.node}"]}
-
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(error_handler=default_handler)
-        .add_node("route_node", route_node)
-        .add_node("fail_a", fail_a, error_handler=node_handler)
-        .add_node("fail_b", fail_b)
-        .add_edge(START, "route_node")
-        .add_conditional_edges(
-            "route_node", lambda s: s["route"], path_map=["fail_a", "fail_b"]
-        )
-        .compile()
-    )
-
-    result_a = graph.invoke({"route": "fail_a", "foo": []})
-    assert result_a["foo"] == ["node_handled_fail_a"]
-    assert "node:fail_a" in captured["handler"]
-    assert "default:fail_a" not in captured["handler"]
-
-    result_b = graph.invoke({"route": "fail_b", "foo": []})
-    assert result_b["foo"] == ["default_handled_fail_b"]
-    assert "default:fail_b" in captured["handler"]
-
-
-def test_set_node_defaults_error_handler_skips_per_node_handler_nodes():
-    """If a per-node error handler itself raises, the default handler must NOT
-    catch it -- the run should fail."""
-
-    class State(TypedDict):
-        foo: str
-
-    def always_failing(state: State) -> State:
-        raise RuntimeError("node boom")
-
-    def broken_handler(state: State, error: NodeError) -> State:
-        raise RuntimeError("handler boom")
-
-    def default_handler(state: State, error: NodeError) -> State:
-        return {"foo": "default recovered"}
-
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(error_handler=default_handler)
-        .add_node("always_failing", always_failing, error_handler=broken_handler)
-        .add_edge(START, "always_failing")
-        .compile()
-    )
-
-    with pytest.raises(RuntimeError, match="handler boom"):
-        graph.invoke({"foo": ""})
-
-
-def test_set_node_defaults_error_handler_failure_fails_run():
-    """When the default handler itself raises, the run fails (no infinite
-    recursion, no double-routing)."""
-
-    class State(TypedDict):
-        foo: str
-
-    def always_failing(state: State) -> State:
-        raise RuntimeError("node boom")
-
-    def broken_default_handler(state: State, error: NodeError) -> State:
-        raise RuntimeError("default handler boom")
-
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(error_handler=broken_default_handler)
-        .add_node("always_failing", always_failing)
-        .add_edge(START, "always_failing")
-        .compile()
-    )
-
-    with pytest.raises(RuntimeError, match="default handler boom"):
-        graph.invoke({"foo": ""})
-
-
-def test_set_node_defaults_error_handler_receives_runnable_config():
-    class State(TypedDict):
-        foo: str
-
-    def always_failing(state: State) -> State:
-        raise RuntimeError("boom")
-
-    captured: dict[str, Any] = {}
-
-    def default_handler(
-        state: State, error: NodeError, config: RunnableConfig
-    ) -> State:
-        captured["thread_id"] = config["configurable"].get("thread_id")
-        return {"foo": "handled"}
-
-    checkpointer = MemorySaver()
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(error_handler=default_handler)
-        .add_node("always_failing", always_failing)
-        .add_edge(START, "always_failing")
-        .compile(checkpointer=checkpointer)
-    )
-
-    thread_id = str(uuid4())
-    result = graph.invoke(
-        {"foo": ""}, config={"configurable": {"thread_id": thread_id}}
-    )
-    assert result["foo"] == "handled"
-    assert captured["thread_id"] == thread_id
-
-
-def test_set_node_defaults_error_handler_collides_with_user_node():
-    class State(TypedDict):
-        foo: str
-
-    def default_handler(state: State, error: NodeError) -> State:
-        return {"foo": "handled"}
-
-    builder = (
-        StateGraph(State)
-        .set_node_defaults(error_handler=default_handler)
-        .add_node("__default_error_handler__", lambda s: s)
-        .add_edge(START, "__default_error_handler__")
-    )
-
-    with pytest.raises(ValueError, match="__default_error_handler__"):
-        builder.compile()
-
-
-def test_set_node_defaults_retry_policy():
-    class State(TypedDict):
-        foo: str
-
-    attempts = 0
-
-    def flaky_node(state: State) -> State:
-        nonlocal attempts
-        attempts += 1
-        if attempts < 3:
-            raise ValueError("not yet")
-        return {"foo": "ok"}
-
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(
-            retry_policy=RetryPolicy(
-                max_attempts=3, initial_interval=0.01, jitter=False, retry_on=ValueError
-            )
-        )
-        .add_node("flaky", flaky_node)
-        .add_edge(START, "flaky")
-        .compile()
-    )
-
-    with patch("time.sleep"):
-        result = graph.invoke({"foo": ""})
-
-    assert result["foo"] == "ok"
-    assert attempts == 3
-
-
-def test_set_node_defaults_retry_policy_per_node_wins():
-    class State(TypedDict):
-        foo: str
-
-    attempts = 0
-
-    def flaky_node(state: State) -> State:
-        nonlocal attempts
-        attempts += 1
-        if attempts < 2:
-            raise ValueError("not yet")
-        return {"foo": "ok"}
-
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(
-            retry_policy=RetryPolicy(
-                max_attempts=1, initial_interval=0.01, jitter=False, retry_on=ValueError
-            )
-        )
-        .add_node(
-            "flaky",
-            flaky_node,
-            retry_policy=RetryPolicy(
-                max_attempts=3,
-                initial_interval=0.01,
-                jitter=False,
-                retry_on=ValueError,
-            ),
-        )
-        .add_edge(START, "flaky")
-        .compile()
-    )
-
-    with patch("time.sleep"):
-        result = graph.invoke({"foo": ""})
-
-    assert result["foo"] == "ok"
-    assert attempts == 2
-
-
-@pytest.mark.anyio
-async def test_set_node_defaults_timeout():
-    class State(TypedDict):
-        foo: str
-
-    async def slow_node(state: State) -> State:
-        await asyncio.sleep(10)
-        return {"foo": "should-not-happen"}
-
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(timeout=TimeoutPolicy(run_timeout=0.05))
-        .add_node("slow", slow_node)
-        .add_edge(START, "slow")
-        .compile()
-    )
-
-    from langgraph.errors import NodeTimeoutError
-
-    with pytest.raises(NodeTimeoutError):
-        await graph.ainvoke({"foo": ""})
-
-
-@pytest.mark.anyio
-async def test_set_node_defaults_timeout_per_node_wins():
-    """Per-node timeout overrides the default; a generous per-node timeout
-    allows a node to complete even when the builder default is very short."""
-
-    class State(TypedDict):
-        foo: str
-
-    async def quick_node(state: State) -> State:
-        await asyncio.sleep(0.05)
-        return {"foo": "done"}
-
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(timeout=TimeoutPolicy(run_timeout=0.01))
-        .add_node("quick", quick_node, timeout=TimeoutPolicy(run_timeout=5.0))
-        .add_edge(START, "quick")
-        .compile()
-    )
-
-    result = await graph.ainvoke({"foo": ""})
-    assert result["foo"] == "done"
-
-
-def test_set_node_defaults_chaining():
-    """set_node_defaults() is chainable and can be called in any order relative to add_node."""
-
-    class State(TypedDict):
-        foo: str
-
-    def always_failing(state: State) -> State:
-        raise RuntimeError("boom")
-
-    def handler(state: State, error: NodeError) -> State:
-        return {"foo": "handled"}
-
-    graph = (
-        StateGraph(State)
-        .add_node("a", always_failing)
-        .add_edge(START, "a")
-        .set_node_defaults(
-            retry_policy=RetryPolicy(
-                max_attempts=1, initial_interval=0.01, jitter=False
-            ),
-            error_handler=handler,
-        )
-        .compile()
-    )
-
-    result = graph.invoke({"foo": ""})
-    assert result["foo"] == "handled"
-
-
-def test_set_node_defaults_combined_retry_and_error_handler():
-    """Retries are exhausted first, then the error handler runs."""
-
-    class State(TypedDict):
-        foo: str
-
-    attempts = 0
-    captured: dict[str, Any] = {}
-
-    def always_failing(state: State) -> State:
-        nonlocal attempts
-        attempts += 1
-        raise ValueError("Always fails")
-
-    def handler(state: State, error: NodeError) -> State:
-        captured["error"] = str(error.error)
-        return {"foo": "handled"}
-
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(
-            retry_policy=RetryPolicy(
-                max_attempts=2,
-                initial_interval=0.01,
-                jitter=False,
-                retry_on=ValueError,
-            ),
-            error_handler=handler,
-        )
-        .add_node("fail", always_failing)
-        .add_edge(START, "fail")
-        .compile()
-    )
-
-    with patch("time.sleep"):
-        result = graph.invoke({"foo": ""})
-
-    assert result["foo"] == "handled"
-    assert attempts == 2
-    assert captured["error"] == "Always fails"
-
-
-def test_error_handler_resumes_after_crash():
-    """If the error handler crashes, resuming should re-schedule the handler
-    (not re-execute the original failed node)."""
-
-    class State(TypedDict):
-        foo: str
-
-    call_count = {"node": 0, "handler": 0}
-    captured_errors: list[NodeError] = []
-
-    def failing_node(state: State) -> State:
-        call_count["node"] += 1
-        raise RuntimeError("boom")
-
-    handler_should_fail = [True]
-
-    def handler(state: State, error: NodeError) -> State:
-        call_count["handler"] += 1
-        captured_errors.append(error)
-        if handler_should_fail[0]:
-            raise RuntimeError("handler crash")
-        return {"foo": "recovered"}
-
-    checkpointer = MemorySaver()
-    graph = (
-        StateGraph(State)
-        .set_node_defaults(error_handler=handler)
-        .add_node("fail", failing_node)
-        .add_edge(START, "fail")
-        .compile(checkpointer=checkpointer)
-    )
-
-    config = {"configurable": {"thread_id": "t1"}}
-
-    # First invoke: node fails -> handler runs -> handler crashes -> run fails
-    with pytest.raises(RuntimeError, match="handler crash"):
-        graph.invoke({"foo": ""}, config)
-
-    assert call_count["node"] == 1
-    assert call_count["handler"] == 1
-    assert captured_errors[0].node == "fail"
-    assert isinstance(captured_errors[0].error, RuntimeError)
-    assert str(captured_errors[0].error) == "boom"
-
-    # Resume: handler should run again, NOT the original node
-    handler_should_fail[0] = False
-    result = graph.invoke(None, config)
-
-    assert result["foo"] == "recovered"
-    assert call_count["node"] == 1  # NOT re-executed
-    assert call_count["handler"] == 2  # ran again on resume
-    # on resume the error was round-tripped through the checkpointer, so it
-    # may be deserialized as a string representation rather than the original
-    # exception type — verify the node name and that the error content matches.
-    assert captured_errors[1].node == "fail"
-    assert "boom" in str(captured_errors[1].error)
-
-
-def test_error_handler_resumes_after_crash_multiple_nodes():
-    """When multiple nodes fail in the same superstep and all have error handlers:
-    - error handlers start running while other nodes may still be in-flight
-    - resuming re-schedules each handler (not re-executes the original nodes)
-    """
-
-    class State(TypedDict):
-        results: Annotated[list[str], operator.add]
-
-    call_count = {"a": 0, "b": 0, "handler_a": 0, "handler_b": 0}
-    handler_a_started = threading.Event()
-
-    def node_a(state: State) -> State:
-        call_count["a"] += 1
-        raise RuntimeError("a failed")
-
-    def node_b(state: State) -> State:
-        call_count["b"] += 1
-        # Block until handler_a has started — proves the error handler runs
-        # concurrently with in-flight nodes in the same superstep.
-        assert handler_a_started.wait(timeout=5), "handler_a never started"
-        raise RuntimeError("b failed")
-
-    handler_should_fail = [True]
-
-    def handler_a(state: State, error: NodeError) -> State:
-        call_count["handler_a"] += 1
-        assert error.node == "a"
-        assert "a failed" in str(error.error)
-        handler_a_started.set()
-        if handler_should_fail[0]:
-            raise RuntimeError("handler_a crash")
-        return {"results": [f"recovered_a:{error.node}"]}
-
-    def handler_b(state: State, error: NodeError) -> State:
-        call_count["handler_b"] += 1
-        assert error.node == "b"
-        assert "b failed" in str(error.error)
-        if handler_should_fail[0]:
-            raise RuntimeError("handler_b crash")
-        return {"results": [f"recovered_b:{error.node}"]}
-
-    checkpointer = MemorySaver()
-    graph = (
-        StateGraph(State)
-        .add_node("a", node_a, error_handler=handler_a)
-        .add_node("b", node_b, error_handler=handler_b)
-        .add_edge(START, "a")
-        .add_edge(START, "b")
-        .compile(checkpointer=checkpointer)
-    )
-
-    config = {"configurable": {"thread_id": "t1"}}
-
-    # First invoke: node_a fails immediately -> handler_a starts (sets event) ->
-    # node_b unblocks and fails -> handler_b starts -> both handlers crash
-    with pytest.raises(RuntimeError):
-        graph.invoke({"results": []}, config)
-
-    assert call_count["a"] == 1
-    assert call_count["b"] == 1
-    assert call_count["handler_a"] == 1
-    assert call_count["handler_b"] == 1
-
-    # Resume: both handlers should run again, NOT the original nodes
-    handler_should_fail[0] = False
-    handler_a_started.clear()
-    result = graph.invoke(None, config)
-
-    assert call_count["a"] == 1  # NOT re-executed
-    assert call_count["b"] == 1  # NOT re-executed
-    assert call_count["handler_a"] == 2  # ran again on resume
-    assert call_count["handler_b"] == 2  # ran again on resume
-    assert "recovered_a:a" in result["results"]
-    assert "recovered_b:b" in result["results"]

libs/langgraph/uv.lock

@@ -1350,7 +1350,7 @@ wheels = [
 
 [[package]]
 name = "langchain-core"
-version = "1.4.0"
+version = "1.4.0a2"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "jsonpatch" },
@@ -1363,9 +1363,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "uuid-utils" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/59/de/679a53472c25860837e32c0442c962fa86e95317a36460e2c9d5c91b17c2/langchain_core-1.4.0.tar.gz", hash = "sha256:1dc341eed802ed9c117c0df3923c991e5e9e226571e5725c194eeb5bd93d1a7f", size = 920260, upload-time = "2026-05-11T18:42:35.919Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/3c/93/68bafa047f8e1770d0cf0f61d6c70889f1dec42ef6bd263540d916c421b9/langchain_core-1.4.0a2.tar.gz", hash = "sha256:b723c7961b615c7f2180ce2bcf352fdad8247bc51a60adecd3d97088235c120d", size = 916486, upload-time = "2026-05-01T15:02:19.029Z" }
 wheels = [
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 ]
 
 [[package]]
@@ -1382,7 +1382,7 @@ wheels = [
 
 [[package]]
 name = "langgraph"
-version = "1.2.0"
+version = "1.2.0a7"
 source = { editable = "." }
 dependencies = [
     { name = "langchain-core" },
@@ -1454,7 +1454,7 @@ test = [
 
 [package.metadata]
 requires-dist = [
-    { name = "langchain-core", specifier = ">=1.4.0,<2" },
+    { name = "langchain-core", specifier = ">=1.4.0a2,<2" },
     { name = "langgraph-checkpoint", editable = "../checkpoint" },
     { name = "langgraph-prebuilt", editable = "../prebuilt" },
     { name = "langgraph-sdk", editable = "../sdk-py" },
@@ -1563,7 +1563,7 @@ wheels = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.1.0"
+version = "4.1.0a4"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },
@@ -1611,7 +1611,7 @@ test = [
 
 [[package]]
 name = "langgraph-checkpoint-postgres"
-version = "3.1.0"
+version = "3.1.0a4"
 source = { editable = "../checkpoint-postgres" }
 dependencies = [
     { name = "langgraph-checkpoint" },
@@ -1658,7 +1658,7 @@ test = [
 
 [[package]]
 name = "langgraph-checkpoint-sqlite"
-version = "3.1.0"
+version = "3.1.0a1"
 source = { editable = "../checkpoint-sqlite" }
 dependencies = [
     { name = "aiosqlite" },
@@ -1757,7 +1757,7 @@ test = [
 
 [[package]]
 name = "langgraph-prebuilt"
-version = "1.1.0"
+version = "1.1.0a2"
 source = { editable = "../prebuilt" }
 dependencies = [
     { name = "langchain-core" },
@@ -2085,14 +2085,14 @@ wheels = [
 
 [[package]]
 name = "mistune"
-version = "3.2.1"
+version = "3.2.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "typing-extensions", marker = "python_full_version < '3.11'" },
 ]
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 ]
 
 [[package]]
@@ -3743,11 +3743,11 @@ wheels = [
 
 [[package]]
 name = "urllib3"
-version = "2.7.0"
+version = "2.6.3"
 source = { registry = "https://pypi.org/simple" }
-sdist = { url = "https://files.pythonhosted.org/packages/53/0c/06f8b233b8fd13b9e5ee11424ef85419ba0d8ba0b3138bf360be2ff56953/urllib3-2.7.0.tar.gz", hash = "sha256:231e0ec3b63ceb14667c67be60f2f2c40a518cb38b03af60abc813da26505f4c", size = 433602, upload-time = "2026-05-07T16:13:18.596Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/c7/24/5f1b3bdffd70275f6661c76461e25f024d5a38a46f04aaca912426a2b1d3/urllib3-2.6.3.tar.gz", hash = "sha256:1b62b6884944a57dbe321509ab94fd4d3b307075e0c2eae991ac71ee15ad38ed", size = 435556, upload-time = "2026-01-07T16:24:43.925Z" }
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 [[package]]

libs/prebuilt/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "langgraph-prebuilt"
-version = "1.1.0"
+version = "1.1.0a2"
 description = "Library with high-level APIs for creating and executing LangGraph agents and tools."
 authors = []
 requires-python = ">=3.10"

libs/prebuilt/uv.lock

@@ -253,7 +253,7 @@ wheels = [
 
 [[package]]
 name = "langchain-core"
-version = "1.4.0"
+version = "1.4.0a2"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "jsonpatch" },
@@ -266,9 +266,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "uuid-utils" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/59/de/679a53472c25860837e32c0442c962fa86e95317a36460e2c9d5c91b17c2/langchain_core-1.4.0.tar.gz", hash = "sha256:1dc341eed802ed9c117c0df3923c991e5e9e226571e5725c194eeb5bd93d1a7f", size = 920260, upload-time = "2026-05-11T18:42:35.919Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/3c/93/68bafa047f8e1770d0cf0f61d6c70889f1dec42ef6bd263540d916c421b9/langchain_core-1.4.0a2.tar.gz", hash = "sha256:b723c7961b615c7f2180ce2bcf352fdad8247bc51a60adecd3d97088235c120d", size = 916486, upload-time = "2026-05-01T15:02:19.029Z" }
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+    { url = "https://files.pythonhosted.org/packages/4e/8e/933e0ba7ba0430ce264e36b178d581b255239ad45093872483142d93478c/langchain_core-1.4.0a2-py3-none-any.whl", hash = "sha256:a5c689f8404357df797120c012da7704144a953b2ae18f258df263301e7badd5", size = 546297, upload-time = "2026-05-01T15:02:17.731Z" },
 ]
 
 [[package]]
@@ -285,7 +285,7 @@ wheels = [
 
 [[package]]
 name = "langgraph"
-version = "1.2.0"
+version = "1.2.0a7"
 source = { editable = "../langgraph" }
 dependencies = [
     { name = "langchain-core" },
@@ -298,7 +298,7 @@ dependencies = [
 
 [package.metadata]
 requires-dist = [
-    { name = "langchain-core", specifier = ">=1.4.0,<2" },
+    { name = "langchain-core", specifier = ">=1.4.0a2,<2" },
     { name = "langgraph-checkpoint", editable = "../checkpoint" },
     { name = "langgraph-prebuilt", editable = "." },
     { name = "langgraph-sdk", editable = "../sdk-py" },
@@ -369,7 +369,7 @@ test = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.1.0"
+version = "4.1.0a4"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },
@@ -417,7 +417,7 @@ test = [
 
 [[package]]
 name = "langgraph-checkpoint-postgres"
-version = "3.1.0"
+version = "3.1.0a4"
 source = { editable = "../checkpoint-postgres" }
 dependencies = [
     { name = "langgraph-checkpoint" },
@@ -464,7 +464,7 @@ test = [
 
 [[package]]
 name = "langgraph-checkpoint-sqlite"
-version = "3.1.0"
+version = "3.1.0a1"
 source = { editable = "../checkpoint-sqlite" }
 dependencies = [
     { name = "aiosqlite" },
@@ -507,7 +507,7 @@ test = [
 
 [[package]]
 name = "langgraph-prebuilt"
-version = "1.1.0"
+version = "1.1.0a2"
 source = { editable = "." }
 dependencies = [
     { name = "langchain-core" },
@@ -1490,11 +1490,11 @@ wheels = [
 
 [[package]]
 name = "urllib3"
-version = "2.7.0"
+version = "2.6.3"
 source = { registry = "https://pypi.org/simple" }
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+sdist = { url = "https://files.pythonhosted.org/packages/c7/24/5f1b3bdffd70275f6661c76461e25f024d5a38a46f04aaca912426a2b1d3/urllib3-2.6.3.tar.gz", hash = "sha256:1b62b6884944a57dbe321509ab94fd4d3b307075e0c2eae991ac71ee15ad38ed", size = 435556, upload-time = "2026-01-07T16:24:43.925Z" }
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+    { url = "https://files.pythonhosted.org/packages/39/08/aaaad47bc4e9dc8c725e68f9d04865dbcb2052843ff09c97b08904852d84/urllib3-2.6.3-py3-none-any.whl", hash = "sha256:bf272323e553dfb2e87d9bfd225ca7b0f467b919d7bbd355436d3fd37cb0acd4", size = 131584, upload-time = "2026-01-07T16:24:42.685Z" },
 ]
 
 [[package]]

libs/sdk-py/langgraph_sdk/_async/cron.py

@@ -18,7 +18,6 @@ from langgraph_sdk.schema import (
     CronSortBy,
     Durability,
     Input,
-    Json,
     OnCompletionBehavior,
     QueryParamTypes,
     Run,
@@ -414,7 +413,6 @@ class CronClient:
         assistant_id: str | None = None,
         thread_id: str | None = None,
         enabled: bool | None = None,
-        metadata: Json = None,
         limit: int = 10,
         offset: int = 0,
         sort_by: CronSortBy | None = None,
@@ -429,8 +427,6 @@ class CronClient:
             assistant_id: The assistant ID or graph name to search for.
             thread_id: the thread ID to search for.
             enabled: The enabled status to search for.
-            metadata: Metadata to filter by. Exact match filter for each KV pair.
-                !!! version-added "Added in Agent Server version 0.9.0"
             limit: The maximum number of results to return.
             offset: The number of results to skip.
             headers: Optional custom headers to include with the request.
@@ -485,8 +481,6 @@ class CronClient:
             "limit": limit,
             "offset": offset,
         }
-        if metadata:
-            payload["metadata"] = metadata
         if sort_by:
             payload["sort_by"] = sort_by
         if sort_order:
@@ -503,7 +497,6 @@ class CronClient:
         *,
         assistant_id: str | None = None,
         thread_id: str | None = None,
-        metadata: Json = None,
         headers: Mapping[str, str] | None = None,
         params: QueryParamTypes | None = None,
     ) -> int:
@@ -512,8 +505,6 @@ class CronClient:
         Args:
             assistant_id: Assistant ID to filter by.
             thread_id: Thread ID to filter by.
-            metadata: Metadata to filter by. Exact match filter for each KV pair.
-                !!! version-added "Added in Agent Server version 0.9.0"
             headers: Optional custom headers to include with the request.
             params: Optional query parameters to include with the request.
 
@@ -525,8 +516,6 @@ class CronClient:
             payload["assistant_id"] = assistant_id
         if thread_id:
             payload["thread_id"] = thread_id
-        if metadata:
-            payload["metadata"] = metadata
         return await self.http.post(
             "/runs/crons/count", json=payload, headers=headers, params=params
         )

libs/sdk-py/langgraph_sdk/_sync/cron.py

@@ -18,7 +18,6 @@ from langgraph_sdk.schema import (
     CronSortBy,
     Durability,
     Input,
-    Json,
     OnCompletionBehavior,
     QueryParamTypes,
     Run,
@@ -403,7 +402,6 @@ class SyncCronClient:
         assistant_id: str | None = None,
         thread_id: str | None = None,
         enabled: bool | None = None,
-        metadata: Json = None,
         limit: int = 10,
         offset: int = 0,
         sort_by: CronSortBy | None = None,
@@ -418,8 +416,6 @@ class SyncCronClient:
             assistant_id: The assistant ID or graph name to search for.
             thread_id: the thread ID to search for.
             enabled: Whether the cron job is enabled.
-            metadata: Metadata to filter by. Exact match filter for each KV pair.
-                !!! version-added "Added in Agent Server version 0.9.0"
             limit: The maximum number of results to return.
             offset: The number of results to skip.
             headers: Optional custom headers to include with the request.
@@ -472,8 +468,6 @@ class SyncCronClient:
             "limit": limit,
             "offset": offset,
         }
-        if metadata:
-            payload["metadata"] = metadata
         if sort_by:
             payload["sort_by"] = sort_by
         if sort_order:
@@ -490,7 +484,6 @@ class SyncCronClient:
         *,
         assistant_id: str | None = None,
         thread_id: str | None = None,
-        metadata: Json = None,
         headers: Mapping[str, str] | None = None,
         params: QueryParamTypes | None = None,
     ) -> int:
@@ -499,8 +492,6 @@ class SyncCronClient:
         Args:
             assistant_id: Assistant ID to filter by.
             thread_id: Thread ID to filter by.
-            metadata: Metadata to filter by. Exact match filter for each KV pair.
-                !!! version-added "Added in Agent Server version 0.9.0"
             headers: Optional custom headers to include with the request.
             params: Optional query parameters to include with the request.
 
@@ -512,8 +503,6 @@ class SyncCronClient:
             payload["assistant_id"] = assistant_id
         if thread_id:
             payload["thread_id"] = thread_id
-        if metadata:
-            payload["metadata"] = metadata
         return self.http.post(
             "/runs/crons/count", json=payload, headers=headers, params=params
         )

libs/sdk-py/tests/test_crons_client.py

@@ -485,165 +485,3 @@ def test_sync_update_with_enabled_parameter(enabled_value):
         )
 
     assert result == cron
-
-
-@pytest.mark.asyncio
-async def test_async_search_with_metadata():
-    """Test that CronClient.search forwards metadata in the request body."""
-    cron = _cron_response()
-
-    async def handler(request: httpx.Request) -> httpx.Response:
-        assert request.method == "POST"
-        assert request.url.path == "/runs/crons/search"
-
-        body = json.loads(request.content)
-        assert body["metadata"] == {"owner": "alice"}
-        assert body["limit"] == 10
-        assert body["offset"] == 0
-
-        return httpx.Response(200, json=[cron])
-
-    transport = httpx.MockTransport(handler)
-    async with httpx.AsyncClient(
-        transport=transport, base_url="https://example.com"
-    ) as client:
-        http_client = HttpClient(client)
-        cron_client = CronClient(http_client)
-        result = await cron_client.search(metadata={"owner": "alice"})
-
-    assert result == [cron]
-
-
-@pytest.mark.asyncio
-async def test_async_search_omits_empty_metadata():
-    """Test that CronClient.search does not send metadata when not provided."""
-    cron = _cron_response()
-
-    async def handler(request: httpx.Request) -> httpx.Response:
-        body = json.loads(request.content)
-        assert "metadata" not in body
-        return httpx.Response(200, json=[cron])
-
-    transport = httpx.MockTransport(handler)
-    async with httpx.AsyncClient(
-        transport=transport, base_url="https://example.com"
-    ) as client:
-        http_client = HttpClient(client)
-        cron_client = CronClient(http_client)
-        await cron_client.search()
-
-
-@pytest.mark.asyncio
-async def test_async_count_with_metadata():
-    """Test that CronClient.count forwards metadata in the request body."""
-
-    async def handler(request: httpx.Request) -> httpx.Response:
-        assert request.method == "POST"
-        assert request.url.path == "/runs/crons/count"
-
-        body = json.loads(request.content)
-        assert body["metadata"] == {"team": "infra"}
-
-        return httpx.Response(200, json=2)
-
-    transport = httpx.MockTransport(handler)
-    async with httpx.AsyncClient(
-        transport=transport, base_url="https://example.com"
-    ) as client:
-        http_client = HttpClient(client)
-        cron_client = CronClient(http_client)
-        result = await cron_client.count(metadata={"team": "infra"})
-
-    assert result == 2
-
-
-@pytest.mark.asyncio
-async def test_async_count_omits_empty_metadata():
-    """Test that CronClient.count does not send metadata when not provided."""
-
-    async def handler(request: httpx.Request) -> httpx.Response:
-        body = json.loads(request.content)
-        assert "metadata" not in body
-        return httpx.Response(200, json=0)
-
-    transport = httpx.MockTransport(handler)
-    async with httpx.AsyncClient(
-        transport=transport, base_url="https://example.com"
-    ) as client:
-        http_client = HttpClient(client)
-        cron_client = CronClient(http_client)
-        await cron_client.count()
-
-
-def test_sync_search_with_metadata():
-    """Test that SyncCronClient.search forwards metadata in the request body."""
-    cron = _cron_response()
-
-    def handler(request: httpx.Request) -> httpx.Response:
-        assert request.method == "POST"
-        assert request.url.path == "/runs/crons/search"
-
-        body = json.loads(request.content)
-        assert body["metadata"] == {"owner": "alice"}
-
-        return httpx.Response(200, json=[cron])
-
-    transport = httpx.MockTransport(handler)
-    with httpx.Client(transport=transport, base_url="https://example.com") as client:
-        http_client = SyncHttpClient(client)
-        cron_client = SyncCronClient(http_client)
-        result = cron_client.search(metadata={"owner": "alice"})
-
-    assert result == [cron]
-
-
-def test_sync_search_omits_empty_metadata():
-    """Test that SyncCronClient.search does not send metadata when not provided."""
-    cron = _cron_response()
-
-    def handler(request: httpx.Request) -> httpx.Response:
-        body = json.loads(request.content)
-        assert "metadata" not in body
-        return httpx.Response(200, json=[cron])
-
-    transport = httpx.MockTransport(handler)
-    with httpx.Client(transport=transport, base_url="https://example.com") as client:
-        http_client = SyncHttpClient(client)
-        cron_client = SyncCronClient(http_client)
-        cron_client.search()
-
-
-def test_sync_count_with_metadata():
-    """Test that SyncCronClient.count forwards metadata in the request body."""
-
-    def handler(request: httpx.Request) -> httpx.Response:
-        assert request.method == "POST"
-        assert request.url.path == "/runs/crons/count"
-
-        body = json.loads(request.content)
-        assert body["metadata"] == {"team": "infra"}
-
-        return httpx.Response(200, json=2)
-
-    transport = httpx.MockTransport(handler)
-    with httpx.Client(transport=transport, base_url="https://example.com") as client:
-        http_client = SyncHttpClient(client)
-        cron_client = SyncCronClient(http_client)
-        result = cron_client.count(metadata={"team": "infra"})
-
-    assert result == 2
-
-
-def test_sync_count_omits_empty_metadata():
-    """Test that SyncCronClient.count does not send metadata when not provided."""
-
-    def handler(request: httpx.Request) -> httpx.Response:
-        body = json.loads(request.content)
-        assert "metadata" not in body
-        return httpx.Response(200, json=0)
-
-    transport = httpx.MockTransport(handler)
-    with httpx.Client(transport=transport, base_url="https://example.com") as client:
-        http_client = SyncHttpClient(client)
-        cron_client = SyncCronClient(http_client)
-        cron_client.count()

libs/sdk-py/uv.lock

@@ -266,7 +266,7 @@ wheels = [
 
 [[package]]
 name = "langchain-core"
-version = "1.4.0"
+version = "1.4.0a2"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "jsonpatch" },
@@ -279,9 +279,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "uuid-utils" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/59/de/679a53472c25860837e32c0442c962fa86e95317a36460e2c9d5c91b17c2/langchain_core-1.4.0.tar.gz", hash = "sha256:1dc341eed802ed9c117c0df3923c991e5e9e226571e5725c194eeb5bd93d1a7f", size = 920260, upload-time = "2026-05-11T18:42:35.919Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/3c/93/68bafa047f8e1770d0cf0f61d6c70889f1dec42ef6bd263540d916c421b9/langchain_core-1.4.0a2.tar.gz", hash = "sha256:b723c7961b615c7f2180ce2bcf352fdad8247bc51a60adecd3d97088235c120d", size = 916486, upload-time = "2026-05-01T15:02:19.029Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/0f/1a/86c38c27b81913a1c6c12448cab55defb5a1097c7dc9a4cea83f55477a2d/langchain_core-1.4.0-py3-none-any.whl", hash = "sha256:23cbbdb46e38ddd1dd5247e6167e96013eae74bea4c5949c550809970a9e565c", size = 548120, upload-time = "2026-05-11T18:42:33.992Z" },
+    { url = "https://files.pythonhosted.org/packages/4e/8e/933e0ba7ba0430ce264e36b178d581b255239ad45093872483142d93478c/langchain_core-1.4.0a2-py3-none-any.whl", hash = "sha256:a5c689f8404357df797120c012da7704144a953b2ae18f258df263301e7badd5", size = 546297, upload-time = "2026-05-01T15:02:17.731Z" },
 ]
 
 [[package]]
@@ -298,7 +298,7 @@ wheels = [
 
 [[package]]
 name = "langgraph"
-version = "1.2.0"
+version = "1.2.0a7"
 source = { editable = "../langgraph" }
 dependencies = [
     { name = "langchain-core" },
@@ -311,7 +311,7 @@ dependencies = [
 
 [package.metadata]
 requires-dist = [
-    { name = "langchain-core", specifier = ">=1.4.0,<2" },
+    { name = "langchain-core", specifier = ">=1.4.0a2,<2" },
     { name = "langgraph-checkpoint", editable = "../checkpoint" },
     { name = "langgraph-prebuilt", editable = "../prebuilt" },
     { name = "langgraph-sdk", editable = "." },
@@ -382,7 +382,7 @@ test = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.1.0"
+version = "4.1.0a4"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },
@@ -430,7 +430,7 @@ test = [
 
 [[package]]
 name = "langgraph-prebuilt"
-version = "1.1.0"
+version = "1.1.0a2"
 source = { editable = "../prebuilt" }
 dependencies = [
     { name = "langchain-core" },