feat: add HTTP-proxy LangGraph checkpointer

Replace direct Postgres checkpointing with HTTP-proxied checkpoint
operations through the agentex backend API. Agents no longer need
DATABASE_URL or direct DB connections for LangGraph state persistence.

- Add HttpCheckpointSaver that proxies through AsyncAgentex client
- Add create_checkpointer() factory using the HTTP checkpointer
- Replace langgraph-checkpoint-postgres dep with langgraph-checkpoint
- Export checkpointer module from adk package

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: 2 people

.release-please-manifest.json

@@ -1,3 +1,3 @@
 {
-  ".": "0.8.2"
+  ".": "0.9.0"
 }

CHANGELOG.md

@@ -1,5 +1,19 @@
 # Changelog
 
+## 0.9.0 (2026-01-21)
+
+Full Changelog: [v0.8.2...v0.9.0](https://github.com/scaleapi/scale-agentex-python/compare/v0.8.2...v0.9.0)
+
+### Features
+
+* **api:** api update ([33ade28](https://github.com/scaleapi/scale-agentex-python/commit/33ade2859c35413ecb4972a68a85cc0ef426e864))
+* **client:** add support for binary request streaming ([07e2881](https://github.com/scaleapi/scale-agentex-python/commit/07e2881a23ad2c624306c8d10ab661ddef42deec))
+
+
+### Chores
+
+* **internal:** update `actions/checkout` version ([64d91f6](https://github.com/scaleapi/scale-agentex-python/commit/64d91f6984c577e0a8a1546bc0f96f944d343a7d))
+
 ## 0.8.2 (2026-01-02)
 
 Full Changelog: [v0.8.1...v0.8.2](https://github.com/scaleapi/scale-agentex-python/compare/v0.8.1...v0.8.2)

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "agentex-sdk"
-version = "0.8.2"
+version = "0.9.0"
 description = "The official Python library for the agentex API"
 dynamic = ["readme"]
 license = "Apache-2.0"
@@ -48,6 +48,7 @@ dependencies = [
     "yaspin>=3.1.0",
     "claude-agent-sdk>=0.1.0",
     "anthropic>=0.40.0",
+    "langgraph-checkpoint>=2.0.0",
 ]
 
 requires-python = ">= 3.12,<4"

requirements-dev.lock

@@ -16,12 +16,16 @@ aiohttp==3.13.2
     # via agentex-sdk
     # via httpx-aiohttp
     # via litellm
-aiosignal==1.3.2
+aiosignal==1.4.0
     # via aiohttp
 annotated-types==0.7.0
     # via pydantic
+anthropic==0.79.0
+    # via agentex-sdk
 anyio==4.10.0
     # via agentex-sdk
+    # via anthropic
+    # via claude-agent-sdk
     # via httpx
     # via mcp
     # via openai
@@ -51,6 +55,8 @@ certifi==2023.7.22
     # via requests
 charset-normalizer==3.4.3
     # via requests
+claude-agent-sdk==0.1.33
+    # via agentex-sdk
 click==8.2.1
     # via litellm
     # via typer
@@ -76,9 +82,12 @@ distlib==0.3.7
     # via virtualenv
 distro==1.9.0
     # via agentex-sdk
+    # via anthropic
     # via openai
     # via scale-gp
     # via scale-gp-beta
+docstring-parser==0.17.0
+    # via anthropic
 envier==0.6.1
     # via ddtrace
 execnet==2.1.1
@@ -108,7 +117,9 @@ httpcore==1.0.9
     # via httpx
 httpx==0.27.2
     # via agentex-sdk
+    # via anthropic
     # via httpx-aiohttp
+    # via langsmith
     # via litellm
     # via mcp
     # via openai
@@ -143,9 +154,14 @@ jinja2==3.1.6
     # via agentex-sdk
     # via litellm
 jiter==0.10.0
+    # via anthropic
     # via openai
 json-log-formatter==1.1.1
     # via agentex-sdk
+jsonpatch==1.33
+    # via langchain-core
+jsonpointer==3.0.0
+    # via jsonpatch
 jsonref==1.1.0
     # via agentex-sdk
 jsonschema==4.25.0
@@ -161,6 +177,12 @@ jupyter-core==5.8.1
     # via jupyter-client
 kubernetes==28.1.0
     # via agentex-sdk
+langchain-core==1.2.9
+    # via langgraph-checkpoint
+langgraph-checkpoint==4.0.0
+    # via agentex-sdk
+langsmith==0.6.9
+    # via langchain-core
 litellm==1.75.5.post1
     # via agentex-sdk
 markdown-it-py==3.0.0
@@ -172,6 +194,7 @@ matplotlib-inline==0.1.7
     # via ipython
 mcp==1.12.4
     # via agentex-sdk
+    # via claude-agent-sdk
     # via openai-agents
 mdurl==0.1.2
     # via markdown-it-py
@@ -199,15 +222,21 @@ openai-agents==0.4.2
     # via agentex-sdk
 opentelemetry-api==1.37.0
     # via ddtrace
+orjson==3.11.7
+    # via langsmith
+ormsgpack==1.12.2
+    # via langgraph-checkpoint
 packaging==23.2
     # via huggingface-hub
     # via ipykernel
+    # via langchain-core
+    # via langsmith
     # via nox
     # via pytest
-pathspec==0.12.1
-    # via mypy
 parso==0.8.4
     # via jedi
+pathspec==0.12.1
+    # via mypy
 pexpect==4.9.0
     # via ipython
 platformdirs==3.11.0
@@ -237,7 +266,10 @@ pyasn1-modules==0.4.2
     # via google-auth
 pydantic==2.11.9
     # via agentex-sdk
+    # via anthropic
     # via fastapi
+    # via langchain-core
+    # via langsmith
     # via litellm
     # via mcp
     # via openai
@@ -283,6 +315,7 @@ pyyaml==6.0.2
     # via agentex-sdk
     # via huggingface-hub
     # via kubernetes
+    # via langchain-core
 pyzmq==27.0.1
     # via ipykernel
     # via jupyter-client
@@ -299,12 +332,16 @@ requests==2.32.4
     # via datadog
     # via huggingface-hub
     # via kubernetes
+    # via langsmith
     # via openai-agents
     # via python-on-whales
     # via requests-oauthlib
+    # via requests-toolbelt
     # via tiktoken
 requests-oauthlib==2.0.0
     # via kubernetes
+requests-toolbelt==1.0.0
+    # via langsmith
 respx==0.22.0
 rich==13.9.4
     # via agentex-sdk
@@ -329,6 +366,7 @@ six==1.16.0
     # via python-dateutil
 sniffio==1.3.1
     # via agentex-sdk
+    # via anthropic
     # via anyio
     # via httpx
     # via openai
@@ -343,6 +381,10 @@ starlette==0.46.2
     # via mcp
 temporalio==1.18.2
     # via agentex-sdk
+tenacity==9.1.4
+    # via langchain-core
+termcolor==3.3.0
+    # via yaspin
 tiktoken==0.11.0
     # via litellm
 time-machine==2.9.0
@@ -374,9 +416,11 @@ types-urllib3==1.26.25.14
 typing-extensions==4.12.2
     # via agentex-sdk
     # via aiosignal
+    # via anthropic
     # via anyio
     # via fastapi
     # via huggingface-hub
+    # via langchain-core
     # via mypy
     # via nexus-rpc
     # via openai
@@ -392,7 +436,6 @@ typing-extensions==4.12.2
     # via temporalio
     # via typer
     # via typing-inspection
-    # via virtualenv
 typing-inspection==0.4.2
     # via pydantic
     # via pydantic-settings
@@ -403,6 +446,9 @@ tzlocal==5.3.1
 urllib3==1.26.20
     # via kubernetes
     # via requests
+uuid-utils==0.14.0
+    # via langchain-core
+    # via langsmith
 uvicorn==0.35.0
     # via agentex-sdk
     # via mcp
@@ -416,7 +462,13 @@ websocket-client==1.8.0
     # via kubernetes
 wrapt==1.17.3
     # via ddtrace
+xxhash==3.6.0
+    # via langsmith
 yarl==1.20.0
     # via aiohttp
+yaspin==3.4.0
+    # via agentex-sdk
 zipp==3.23.0
     # via importlib-metadata
+zstandard==0.25.0
+    # via langsmith