Introduction
The capabilities of giant language fashions (LLMs) are advancing quickly. They permit us to construct quite a lot of LLM functions. These vary from process automation to workflow optimization. One thrilling software is utilizing LLMs to create an clever information digest or publication agent. This agent can pull in related content material, summarize it, and ship it in a custom-made format. It may work together dynamically with exterior instruments and knowledge sources to fetch related info. On this article, allow us to discover ways to construct a information digest agent for a customized each day information digest with LangGraph and exterior instruments like Information API.

Overview
- Perceive the structure of LangGraph and its key parts (State, Nodes, and Edges) to construct customizable workflow brokers.
- Learn to combine exterior APIs like NewsAPI to fetch real-time knowledge for dynamic content material technology in newsletters.
- Develop the abilities to make use of LLMs for content material analysis by implementing a scoring system that ranks information articles based mostly on high quality standards.
- Achieve sensible information of automating e mail supply with curated content material utilizing Python’s email-sending libraries.
Temporary About LangGraph
LangGraph is constructed on prime of LangChain. LangGraph is a framework designed for constructing dynamic workflows that combine LLMs with customized logic and instruments. This permits for extremely custom-made and sophisticated workflows that mix a number of instruments and APIs.
LangGraph consists of three core parts:
- State: The State accommodates the info that’s shared all through the applying. It may be any Python knowledge construction that may maintain the info. We are able to outline it utilizing a State object with totally different parameters. Alternatively, we are able to additionally use pre-built MessagesState which might include solely an inventory of messages.
- Nodes: Nodes are features that may learn and modify the State. These features take the State as the primary argument to learn or write to the State. We even have a START node to indicate which node will take the consumer enter and be referred to as first and an END node to indicate the tip of the graph.
- Edges: Edges outline the stream of knowledge via totally different nodes. We even have conditional edges which use a operate to find out which node to go to subsequent. The benefit of LangGraph is that we are able to customise the agent in some ways. So, there might be multiple technique to construct this agent.

As proven within the picture, edges join nodes, and nodes learn or write the info within the State.
Additionally Learn: Optimize Your Organisation’s Electronic mail Advertising with GenAI Brokers
Conditions
Earlier than we begin constructing the LLM agent, let’s ensure that we’ve got the required keys and passwords.
Accessing an LLM through API
Start by producing an API key for the LLM you’re utilizing. Create a textual content file with the title ‘.env’. Retailer this key securely in a .env file to maintain it non-public and simply accessible inside your mission.
Right here’s an instance of how a .env file appears to be like like

Fetching Information Knowledge
To assemble information content material, we’ll use https://newsapi.org/. Join an API key and retailer it in the identical .env file for safe entry.
Sending the Electronic mail
To ship e mail utilizing Python, we are able to allow ‘much less safe apps’ and retailer the Gmail password within the .env file. If that possibility shouldn’t be obtainable, we are able to achieve entry to Gmail by following the steps talked about right here.
Libraries Required
We have now used the next variations for the key libraries:
- langchain – 0.2.14
- langgraph – 0.2.14
- langchain-openai – 0.1.14
- newsapi-python – 0.2.7
Outline the Software Movement
The purpose is to question the agent utilizing pure language to assemble information on a selected subject and get the publication through e mail. To implement this stream, we’ll first outline three instruments to deal with every key process after which construct the agent to name the LLM and instruments.
The three instruments are as follows:
- Fetching the Information: The Information API retrieves related information articles based mostly on the parsed question.
- Scoring the Information: The fetched articles are handed to a different LLM, which evaluates and scores them for high quality. The output is an inventory of articles sorted by their high quality rating.
- Delivering the Information: The highest-scoring articles are formatted right into a well-readable e mail and despatched to the consumer.
Now we are able to begin defining the features.
Get Information
Import the required libraries and cargo the .env file
import os
import json
import pandas as pd
from datetime import datetime, timedelta
from IPython.show import Picture, show
from typing import Listing, Literal, Non-compulsory, TypedDict, Annotated
from langchain_core.instruments import software
from langchain_openai import ChatOpenAI
from dotenv import load_dotenv
load_dotenv('/.env')
# various to the .env file we are able to additionally use the .txt file as follows
with open('mykey.txt', 'r') as file:
openai_key = file.learn()
os.environ['OPENAI_API_KEY'] = openai_key
Provoke the news_api from NewsApiClient and API key
from newsapi import NewsApiClient
NEWS_API_KEY = os.environ['NEWS_API_KEY']
news_api = NewsApiClient(api_key=NEWS_API_KEY)
Now let’s outline the LangChain software utilizing the ‘software’ decorator from LangChain
@software
def get_news(question: str, past_days: int, domains: str):
"""
Get information on the given parameters like question, past_days, and so forth.
Args:
question: search information about this subject
past_days: For what number of days prior to now ought to we search?
domains: search information in these sources
"""
right now = datetime.right now()
from_date = right now - timedelta(days=past_days)
news_details = news_api.get_everything(q=question, from_param=from_date, domains=domains,
sort_by='relevancy')
return news_details
The agent also can kind the articles based mostly on relevancy. Right here’s an instance of how the output of this operate appears to be like like:

‘@software’ decorator is used to outline langchain software. Then we are able to bind this software to the LLM. Within the above operate, the doc string can be vital. That’s what will get handed to the LLM as a immediate to have these arguments within the output of the tool-calling LLM.
# initialize the LLM
gpt = ChatOpenAI(mannequin="gpt-4o-mini", temperature=0)
# we are able to bind the software to the LLM in order that the LLM can return the software based mostly on the question.
gpt_with_tools = gpt.bind_tools([get_news])
Rating Information
The score_news operate processes information articles by scoring them based mostly on predefined standards. Then the operate returns a sorted listing of the highest-quality articles.
Import the required strategies
from langchain_core.pydantic_v1 import BaseModel, Discipline
from langchain_core.prompts import ChatPromptTemplate, PromptTemplate
from langchain_core.messages import HumanMessage
Allow us to outline the operate
def score_news(news_details: dict):
"""
Calculate rating for news_articles and type them by the rating.
news_details: all of the information articles
"""
# entry the final message of the state for the articles.
# passing all of the articles to the LLM will improve the associated fee.
# we are able to select to attain just some articles.
json_articles = json.hundreds(news_details['messages'][-1].content material)['articles']
if len(json_articles) > 15:
articles = json_articles[:15]
else:
articles = json_articles
# system immediate to information the LLM to attain the articles.
system_prompt = """
You're a information high quality evaluator.
I'll offer you a information article, with a title, description, and truncated content material and different particulars.
Analyze and rating the information article based mostly on the next standards:
Readability: How nicely the article conveys the message in a concise and comprehensible method.
Scale: 1 (unclear) to 25 (very clear)
Credibility: Based mostly on the outline and different particulars supplied, how probably is the article to be credible and factually correct?
Scale: 1 (not credible) to 25 (extremely credible)
Engagement potential: How probably the article is to seize the reader's consideration or provoke additional thought.
Scale: 1 (not partaking) to 25 (very partaking)
Affect: How vital or influential the article is by way of its potential societal, technological, or political penalties.
Scale: 1 (minimal affect) to 25 (excessive affect)
Present the full rating out of 100 for the information article, including the scores for every of the above standards.
You may be evaluating loads information articles. So, rating them such that we are able to kind all of them later.
"""
prompt_template = ChatPromptTemplate.from_messages([("system", system_prompt), ("human", "{news}")])
# outline pydantic class to get the output in a structured format.
class Information(BaseModel):
"""Information scoring system"""
total_score: int = Discipline(description='whole rating for the information article')
supply: str = Discipline(description="The supply of the information")
creator: Non-compulsory[str] = Discipline(default=None, description="The creator to the information")
title: str = Discipline(description="The title of the information")
description: str = Discipline(description="The outline to the information")
url: str = Discipline(description="The url of the information")
urlToImage: Non-compulsory[str] = Discipline(default=None, description="The picture url of the information")
# GPT 4o performs higher at scoring however extra pricey.
gpt_4o = ChatOpenAI(mannequin="gpt-4o", temperature=0)
structured_gpt = gpt_4o.with_structured_output(Information)
chain = prompt_template | structured_gpt
# ship every article to the LLM to get the rating with the opposite particulars.
outcomes = [chain.invoke({'news': article}).dict() for article in articles]
# kind the articles by whole rating.
df = pd.DataFrame(outcomes).sort_values(by='total_score', ascending=False)
return {"messages": [HumanMessage(content=df.to_dict(orient="records"))]}
The operate takes the state because the enter with the title as news_details. Because the state has all of the messages, we are able to entry the final message for the articles. We are able to select to attain just some articles from the highest to avoid wasting the prices. We are able to strive totally different system prompts to get one of the best scoring system.
It’s simpler to course of the info if the output is in an outlined format. So, we are able to use LLM with structured output, the place the construction is outlined utilizing the Pydantic class.
Then we are able to rating every article and retailer them in a dataframe. As soon as we kind the articles utilizing the full rating and add them as a message to the state.
Clarification
1. Enter
The operate receives the state object as enter, which accommodates all messages. The most recent message from this state holds the information articles. To reduce prices, as an alternative of scoring all articles, we are able to restrict the variety of articles.
2. Scoring Course of
We offer an in depth system immediate to the LLM, instructing it to attain every article based mostly on the factors given within the system immediate.
The LLM evaluates every article based mostly on the factors outlined within the system immediate and assigns a complete rating out of 100, including scores of every criterion.
3. Structured Output
To make sure the output is structured and simple to course of, we outline a Pydantic mannequin (Information). This mannequin consists of fields like `total_score`, `title`, `description`, and `url`. By utilizing this structured format, the LLM can return constant, well-organized outcomes.
4. LLM Integration
We use GPT-4o, identified for its accuracy in structured duties, to attain the articles. It’s discovered that GPT-4o is best than GPT-4o-mini in ranking the articles. Every article is handed via the LLM, and the outcomes are transformed right into a dictionary format utilizing Pydantic.
5. Sorting and Output
After scoring all of the articles, we retailer them in a Pandas DataFrame, kind them by their `total_score` in descending order. Then we are able to return the sorted listing as a message to the State, prepared for use within the subsequent a part of the workflow.
Ship Electronic mail
The send_email operate takes an inventory of sorted information articles, generates an HTML e mail, and sends it to the recipient.
Import the libraries
import smtplib, ssl
import base64
import e mail
outline the send_email operate
def send_email(sorted_news):
# get the sorted information from the final message of the state.
articles = sorted_news['messages'][-1].content material
# If the news_article has picture, we are able to show it within the e mail.
news_items_html = ""
for article in articles[:10]:
if article['urlToImage'] shouldn't be None:
news_items_html += f"""
"""
else:
news_items_html += f"""
"""
# CSS for styling the HTML message. we add the above 'news_items_html' right here.
html = f"""
"""
port = 465 # For SSL
sender_email = "[email protected]"
password = os.environ['GMAIL_PASSWORD']
context = ssl.create_default_context()
# add the content material for the e-mail
mail = e mail.message.EmailMessage()
mail['To'] = "[email protected]"
mail['From'] = "[email protected]"
mail['Subject'] = "Information Digest"
mail.set_content(html, subtype="html")
with smtplib.SMTP_SSL("smtp.gmail.com", port, context=context) as server:
server.login(sender_email, password)
server.send_message(mail)
Clarification
1. Extracting Sorted Information
The operate begins by accessing the sorted information articles from the final message within the State. We restrict the variety of articles displayed within the e mail to the highest 10.
2. Producing HTML Content material
The operate dynamically constructs the HTML for every information article. If an article consists of a picture (`urlToImage`), the picture is embedded within the e mail subsequent to the article’s title, hyperlink, and outline. In any other case, solely the title and outline are displayed. This HTML block (`news_items_html`) is generated utilizing a loop that processes every article.
3. HTML and CSS Styling
The HTML e mail is styled utilizing embedded CSS to make sure a visually interesting format. The kinds cowl:
- Container: The principle e mail content material is wrapped in a centered container with a white background and refined shadow.
- Information Gadgets: Every information article is displayed with its title (as a clickable hyperlink), description, and optionally a picture. The format makes use of flexbox to align the picture and textual content aspect by aspect, with a border separating every information merchandise.
4. Composing the Electronic mail
The e-mail is about up utilizing Python’s `e mail.message.EmailMessage` class. The HTML content material, topic line (“Information Digest”), sender, and recipient are specified. The HTML is included as the principle content material utilizing `mail.set_content(html, subtype=’html’)`.
5. Sending the Electronic mail
The operate makes use of Gmail’s SMTP server to ship the e-mail securely through SSL (port 465). The sender’s Gmail credentials are fetched from the atmosphere variable `GMAIL_PASSWORD` to keep away from hardcoding delicate info. After logging into the SMTP server, the e-mail is shipped to the recipient.
Constructing the Agent
Allow us to construct the agent based mostly on the instruments and features outlined above.
Step 1. Defining features to name the fashions and instruments.
from langgraph.prebuilt import ToolNode
from langgraph.graph import StateGraph, MessagesState, START, END
# operate to name the mannequin which return the software based mostly on the question.
def call_model(state: MessagesState):
messages = state["messages"]
response = gpt_with_tools.invoke(messages)
return {"messages": [response]}
# if the final message from the above LLM is tool_calls then we return "instruments"
def call_tools(state: MessagesState) -> Literal["tools", END]:
messages = state["messages"]
last_message = messages[-1]
if last_message.tool_calls:
return "instruments"
return END
Step 2. Constructing the workflow graph. Now we are able to use all of the outlined features to construct the agent.
#create a software node with operate in order that we are able to use this within the graph.
get_news_tool = ToolNode([get_news])
workflow = StateGraph(MessagesState)
# We begin the agent from the call_model operate.
workflow.add_node("LLM", call_model)
workflow.add_edge(START, "LLM")
# Add the get_news_tool, which is known as from the above LLM based mostly on the question.
workflow.add_node("instruments", get_news_tool)
workflow.add_conditional_edges("LLM", call_tools)
# then we connect with the score_news operate from get_news operate
workflow.add_node("rating", score_news)
workflow.add_edge("instruments", "rating")
# then we connect with the send_email operate from score_news operate
workflow.add_node("mail", send_email)
workflow.add_edge("rating", "mail")
# we are able to finish with the agent after sending the mail
workflow.add_edge("mail", END)
Step 3. Compiling the graph.
agent = workflow.compile()
show(Picture(agent.get_graph().draw_mermaid_png()))

Now we are able to name the agent with a question.
let’s use a question that has fewer information to print the outputs at every step of the agent.
question = "what is the information on Inidan cricket crew prior to now month from cricinfo?"
# this question will go the START node.
inputs = {"messages": [("user", query)]}
async for chunk in agent.astream(inputs, stream_mode="values"):
chunk["messages"][-1].pretty_print()
The output can be within the format proven beneath. If no articles are returned, we are able to change the question.

As we are able to see, we begin with the question. The LLM will then name the software ‘get_news’. Then, the software returns all of the articles. The ‘score_news’ operate will then course of them and output an inventory of articles with scores. Then ‘send_email’ operate sends the e-mail, although there isn’t a output within the state.
On this manner, we are able to question the agent about any subject and get an e mail with curated information.
Conclusion
Constructing a publication agent utilizing LangGraph and LLMs affords a robust technique to automate information curation and supply. By combining real-time knowledge, clever scoring, and customized e mail supply, this method streamlines the creation of custom-made newsletters, enhancing reader engagement and content material relevance effortlessly.
Steadily Requested Questions
A. LangGraph is a framework for constructing dynamic workflows that combine giant language fashions (LLMs) with customized logic. It permits builders to outline workflows as graphs utilizing States, Nodes, and Edges, the place every Node represents a operate or process, and Edges outline the stream of knowledge between these duties.
A. LangGraph consists of three core parts: State, which holds knowledge shared throughout the applying; Nodes, which symbolize particular person features that learn or modify the State; and Edges, which outline the stream of knowledge between Nodes. Conditional Edges enable for versatile, decision-based workflows.
A. Sure, LangGraph can combine exterior APIs and instruments. You possibly can outline Nodes to deal with particular duties, akin to making API calls or interacting with third-party providers, after which use these Nodes throughout the workflow to create dynamic, real-time functions.
A. LangGraph permits you to outline conditional Edges, which use a operate to find out the subsequent step within the workflow. This function makes it simple to deal with complicated, decision-based eventualities the place the stream is determined by particular situations or consumer enter.