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How to Set Up a LangGraph Application for Deployment

A LangGraph application must be configured with a LangGraph API configuration file in order to be deployed to LangGraph Cloud (or to be self-hosted). This how-to guide discusses the basic steps to setup a LangGraph application for deployment using pyproject.toml to define your package's dependencies.

This walkthrough is based on this repository, which you can play around with to learn more about how to setup your LangGraph application for deployment.

Setup with requirements.txt

If you prefer using requirements.txt for dependency management, check out this how-to guide.

Setup with a Monorepo

If you are interested in deploying a graph located inside a monorepo, take a look at this repository for an example of how to do so.

The final repo structure will look something like this:

my-app/
├── my_agent # all project code lies within here
   ├── utils # utilities for your graph
      ├── __init__.py
      ├── tools.py # tools for your graph
      ├── nodes.py # node functions for you graph
      └── state.py # state definition of your graph
   ├── __init__.py
   └── agent.py # code for constructing your graph
├── .env # environment variables
├── langgraph.json  # configuration file for LangGraph
└── pyproject.toml # dependencies for your project

After each step, an example file directory is provided to demonstrate how code can be organized.

Specify Dependencies

Dependencies can optionally be specified in one of the following files: pyproject.toml, setup.py, or requirements.txt. If none of these files is created, then dependencies can be specified later in the LangGraph API configuration file.

The dependencies below will be included in the image, you can also use them in your code, as long as with a compatible version range:

langgraph>=0.2.56,<0.3.0
langgraph-checkpoint>=2.0.5,<3.0
langchain-core>=0.2.38,<0.4.0
langsmith>=0.1.63
orjson>=3.9.7
httpx>=0.25.0
tenacity>=8.0.0
uvicorn>=0.26.0
sse-starlette>=2.1.0
uvloop>=0.18.0
httptools>=0.5.0
jsonschema-rs>=0.16.3
croniter>=1.0.1
structlog>=23.1.0
redis>=5.0.0,<6.0.0

Example pyproject.toml file:

[tool.poetry]
name = "my-agent"
version = "0.0.1"
description = "An excellent agent build for LangGraph cloud."
authors = ["Polly the parrot <1223+polly@users.noreply.github.com>"]
license = "MIT"
readme = "README.md"

[tool.poetry.dependencies]
python = ">=3.9.0,<3.13"
langgraph = "^0.2.0"
langchain-fireworks = "^0.1.3"


[build-system]
requires = ["poetry-core"]
build-backend = "poetry.core.masonry.api"

Example file directory:

my-app/
└── pyproject.toml   # Python packages required for your graph

Specify Environment Variables

Environment variables can optionally be specified in a file (e.g. .env). See the Environment Variables reference to configure additional variables for a deployment.

Example .env file:

MY_ENV_VAR_1=foo
MY_ENV_VAR_2=bar
FIREWORKS_API_KEY=key

Example file directory:

my-app/
├── .env             # file with environment variables
└── pyproject.toml

Define Graphs

Implement your graphs! Graphs can be defined in a single file or multiple files. Make note of the variable names of each CompiledGraph to be included in the LangGraph application. The variable names will be used later when creating the LangGraph API configuration file.

Example agent.py file, which shows how to import from other modules you define (code for the modules is not shown here, please see this repo to see their implementation):

# my_agent/agent.py
from typing import Literal
from typing_extensions import TypedDict

from langgraph.graph import StateGraph, END, START
from my_agent.utils.nodes import call_model, should_continue, tool_node # import nodes
from my_agent.utils.state import AgentState # import state

# Define the config
class GraphConfig(TypedDict):
    model_name: Literal["anthropic", "openai"]

workflow = StateGraph(AgentState, config_schema=GraphConfig)
workflow.add_node("agent", call_model)
workflow.add_node("action", tool_node)
workflow.add_edge(START, "agent")
workflow.add_conditional_edges(
    "agent",
    should_continue,
    {
        "continue": "action",
        "end": END,
    },
)
workflow.add_edge("action", "agent")

graph = workflow.compile()

Assign CompiledGraph to Variable

The build process for LangGraph Cloud requires that the CompiledGraph object be assigned to a variable at the top-level of a Python module.

Example file directory:

my-app/
├── my_agent # all project code lies within here
   ├── utils # utilities for your graph
      ├── __init__.py
      ├── tools.py # tools for your graph
      ├── nodes.py # node functions for you graph
      └── state.py # state definition of your graph
   ├── __init__.py
   └── agent.py # code for constructing your graph
├── .env
└── pyproject.toml

Create LangGraph API Config

Create a LangGraph API configuration file called langgraph.json. See the LangGraph CLI reference for detailed explanations of each key in the JSON object of the configuration file.

Example langgraph.json file:

{
  "dependencies": ["."],
  "graphs": {
    "agent": "./my_agent/agent.py:graph"
  },
  "env": ".env"
}

Note that the variable name of the CompiledGraph appears at the end of the value of each subkey in the top-level graphs key (i.e. :<variable_name>).

Configuration Location

The LangGraph API configuration file must be placed in a directory that is at the same level or higher than the Python files that contain compiled graphs and associated dependencies.

Example file directory:

my-app/
├── my_agent # all project code lies within here
   ├── utils # utilities for your graph
      ├── __init__.py
      ├── tools.py # tools for your graph
      ├── nodes.py # node functions for you graph
      └── state.py # state definition of your graph
   ├── __init__.py
   └── agent.py # code for constructing your graph
├── .env # environment variables
├── langgraph.json  # configuration file for LangGraph
└── pyproject.toml # dependencies for your project

Next

After you setup your project and place it in a github repo, it's time to deploy your app.

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