LangGraph API

This package implements the LangGraph API for rapid development and testing. Build and iterate on LangGraph agents with a tight feedback loop. The server is backed by a predominently in-memory data store that is persisted to local disk when the server is restarted.

For production use, see the various deployment options for the LangGraph API, which are backed by a production-grade database.

Installation

Install the langgraph-cli package with the inmem extra. Your CLI version must be no lower than 0.1.55.

pip install -U "langgraph-cli[inmem]"

Quickstart

(Optional) Clone a starter template:

langgraph new --template new-langgraph-project-python ./my-project
cd my-project

(Recommended) Use a virtual environment and install dependencies:

python -m venv .venv
source .venv/bin/activate
python -m pip install .

Start the development server:

langgraph dev --config ./langgraph.json

The server will launch, opening a browser window with the graph UI. Interact with your graph or make code edits; the server automatically reloads on changes.

Usage

Start the development server:

langgraph dev

Your agent's state (threads, runs, assistants) persists in memory while the server is running - perfect for development and testing. Each run's state is tracked and can be inspected, making it easy to debug and improve your agent's behavior.

How-To

Attaching a debugger

Debug mode lets you attach your IDE's debugger to the LangGraph API server to set breakpoints and step through your code line-by-line.

Install debugpy:
```
pip install debugpy
```
Start the server in debug mode:
```
langgraph dev --debug-port 5678
```

Configure your IDE:

VS Code: Add this launch configuration:

{
  "name": "Attach to LangGraph",
  "type": "debugpy",
  "request": "attach",
  "connect": {
           "host": "0.0.0.0",
           "port": 5678
       },
}

PyCharm: Use "Attach to Process" and select the langgraph process

Set breakpoints in your graph code and start debugging.

CLI options

langgraph dev [OPTIONS]
Options:
  --debug-port INTEGER         Enable remote debugging on specified port
  --no-browser                 Skip opening browser on startup
  --n-jobs-per-worker INTEGER  Maximum concurrent jobs per worker process
  --config PATH               Custom configuration file path
  --no-reload                 Disable code hot reloading
  --port INTEGER              HTTP server port (default: 8000)
  --host TEXT                 HTTP server host (default: localhost)

License

This project is licensed under the Elastic License 2.0 - see the LICENSE file for details.

Release files for langgraph-api 0.14.0rc2

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for langgraph-api 0.14.0rc2
File	Size	Uploaded
langgraph_api-0.14.0rc2.tar.gz	810.6 kB	Aug 24, 2026	Details

Built distribution (wheel)

Table of built distributions (wheels) for langgraph-api 0.14.0rc2
File	Interpreter	ABI	Platform	Reset
langgraph_api-0.14.0rc2-py3-none-any.whl 621.2 kB Aug 24, 2026	Python 3	none	any	Details

Total release size: 1.4 MB

Release files / langgraph_api-0.14.0rc2.tar.gz

Download URL	langgraph_api-0.14.0rc2.tar.gz
Size	810.6 kB
Tags	Source
SHA-256 checksum How to use checksums	`f7356cbd44dc54c1586bc058fde1faa6ad4195108ee7daca551c95eec043056e`
BLAKE2b-256 checksum How to use checksums	`282afd7bb3ce377ced2368bff20025756697d5ddbbc7f1505eff8383b9e2de29`
Upload date	Aug 24, 2026
Uploaded using Trusted Publishing? What is trusted publishing?	Yes
Uploaded via	`twine/6.1.0 CPython/3.13.13`

Release files / langgraph_api-0.14.0rc2-py3-none-any.whl

Download URL	langgraph_api-0.14.0rc2-py3-none-any.whl
Size	621.2 kB
Tags	Python 3
SHA-256 checksum How to use checksums	`892784b23fa29b3fbde20e6b7c6ca34ffb2e53ca98f34c8bd05ca884a1cd362a`
BLAKE2b-256 checksum How to use checksums	`4bfa8c64e2812b4cd248d38feed7adfdd01db7e0a1b3b8369d1b8c27d21cd5ed`
Upload date	Aug 24, 2026
Uploaded using Trusted Publishing? What is trusted publishing?	Yes
Uploaded via	`twine/6.1.0 CPython/3.13.13`