LangChain

Top Builders

Explore the top contributors showcasing the highest number of app submissions within our community.

LangChain

Large language models (LLMs) are emerging as a transformative technology, enabling developers to build applications that they previously could not. But using these LLMs in isolation is often not enough to create a truly powerful app - the real power comes when you are able to combine them with other sources of computation or knowledge. This library is aimed at assisting in the development of those types of applications.

General
Repository	https://github.com/hwchase17/langchain
Type	Large Language Model framework

LangChain - Resources

Resources to get stared with LangChain

LangChain GitHub Repository
Documentation Documentation for LangChain

LangChain - Use cases

Use cases for LangChain

Question Answering over specific documents Documentation for Question Answering over specific documents
Chatbots Documentation for Chatbots build with LangChain
Agents Documentation for Agents systems build with LangChain

LangChain - Example Projects

Implementations of LangChain

Question Answering on Financial Data PDFs Chat with financial documents (quarterly investor update PDFs) in this case
Code Understanding - Chat with GitHub repo Chat with any number of codebases with context
Question Answering over Notion Database Ask questions to your Notion database in natural language
Chat-LangChain Implementation of a locally hosted chatbot specifically focused on question answering over the LangChain documentation
GPT+WolframAlpha Demonstrates a conversational agent implemented with OpenAI GPT3 and LangChain

Edit on GitHub

Langchain AI Technologies Hackathon projects

Discover innovative solutions crafted with Langchain AI Technologies, developed by our community members during our engaging hackathons.

RevDev

CaliSignal is an AI SDR and GTM intelligence platform built for California startups. It uses Bright Data live web signals to discover high-fit accounts, detect buying windows, score ICP match, and identify the right stakeholders before competitors reach them. The platform turns fragmented public signals like funding news, hiring activity, job posts, reviews, and web changes into prioritized pipeline, account briefs, outreach drafts, alerts, and action workflows. Instead of making SDRs manually research accounts, CaliSignal gives teams a live revenue cockpit that shows who to contact, why now, what to say, and what action to take next.

Verified News

**Verified News** is a real-time narrative verification platform that combats misinformation by autonomously fact-checking claims against live web data, social signals, community notes, and fact-checking databases. Where services like Ground News show *bias*, Verified News answers a harder question: **is it true?** The platform deploys a multi-agent swarm built on **CrewAI**, powered by **Bright Data's** full web data infrastructure (MCP Server, SERP API, Web Unlocker, Scraping Browser, Web Scraper API), with all reasoning running through **AI/ML API** and **Gemma 4 31B**. Verdicts are delivered as color-coded trust badges (🔵 Blue, 🟢 Green, 🟡 Yellow, 🟠 Orange, 🔴 Red, ⚪ Gray) with full evidentiary transparency. For **enterprises**, Verified News is two products in one: - ** Security & Compliance:** A threat intelligence layer that detects disinformation campaigns, false product recall rumors, fake executive statements, and leaked data narratives before they crater stock prices or trigger regulatory action. - ** GTM Intelligence:** A brand health and competitive intelligence platform that verifies market narratives and competitor claims, giving revenue teams accurate ground truth for messaging and positioning.

PulseSignal: Executive GTM Strategy Engine

PulseSignal is a next-generation Market Intelligence platform built for Go-To-Market (GTM) and Sales teams. The platform solves the problem of 'lagging indicators' by treating unstructured web data—specifically high-velocity hiring and news—as leading indicators of corporate strategy. Our autonomous pipeline executes in three stages: 1. Live Data Intercept: Powered by Bright Data SERP API, we perform targeted crawls of Google Search and career pages. 2. Data Structuring: Google Gemini Flash parses messy HTML into strict JSON, identifying niche skills and business priorities. 3. Executive Synthesis: We implemented a Hybrid Multi-Model Architecture, routing complex reasoning through DeepSeek V4 Flash (via AI/ML API) to generate persona-specific playbooks for Sales, Recruiting, and Investors. Key features include a dynamic 'Manager's Weekly Report' with an Account Prioritization Matrix, an Evidence Ledger for transparency, and a 'Magic, Moment' Gmail integration that takes an AI-drafted email and pre-loads it, directly into the user's browser, ready to send. PulseSignal doesn't just show data; it generates quantifiable ROI.

WellSignal

WellnessSignal is a dual-sided GTM intelligence platform that uses live web data to connect wellness operators with corporate buyers. For wellness operators (yoga studios, retreat organizers, dance organisers, coaches): WellSignal scrapes real-time data from ClassPass, Eventbrite, Luma, and Google to surface competitor pricing, demand spikes, and corporate buyers actively hiring for employee wellbeing roles — then recommends exactly what bundles to offer, at what price, and drafts the outreach email. For corporate HR teams: WellSignal scans the wellness market, benchmarks what peer companies offer employees, and builds curated multi-service wellness bundles (yoga + breathwork + coaching + retreats) with ROI projections backed by industry benchmarks. Built on Bright Data's Web Unlocker and SERP API for live scraping, and Claude AI for signal classification, competitor analysis, and bundle recommendations. The global corporate wellness market hits $100B by 2026 — WellSignal is the intelligence layer it's missing.

Misaki: AI Legislative Intelligence Platform

Misaki is an AI-powered legislative and regulatory intelligence platform that tells companies which laws will cost them money — before those laws pass. Today, compliance teams discover threatening bills weeks too late, and incumbents like Quorum, FiscalNote, and LexisNexis only tell you that a bill changed — never what it means for your specific company, what it will cost, or what to do about it. A human lawyer still does all of that by hand. Misaki closes that gap. You give it a company profile (auto-built from the web), and it continuously monitors legislation across 50 US states, the EU, and the UK. For every bill it reasons over the full text against your company, highlights the exact triggering clause, scores pass probability, and estimates dollar exposure. Then it acts — autonomously finding specialized law firms, drafting a lobbyist response brief, and building a competitive strategy — before rendering a board-ready PDF in under nine seconds. All live web intelligence flows through the Bright Data MCP Server: Web Unlocker pulls SEC EDGAR filings, the SERP API reads press coverage, the Web Scraper API traces lobbyist money, and the Scraping Browser handles JS-rendered sources. Every reasoning task is routed through the AI/ML API to the optimal model — gpt-4o-mini triages cheaply, gpt-4.1 reasons over full bills, and gpt-4o drafts responses and reads scanned bills via vision OCR. Deployed live on Vercel and Railway, Misaki is 10× cheaper than incumbents — and the only platform that reasons, prices, and acts.

Vendor Risk Radar

Enterprises depend on dozens of third-party vendors, and when one is breached they usually learn from the news - weeks too late. The hardest part isn't a single vendor; modern breaches cascade. One stolen OAuth token (Salesloft-Drift), one compromised identity provider (Okta), one poisoned dependency silently spreads to every connected vendor. Companies have a vendor list but no visibility into the connections between vendors - so they can't answer the question that matters: which of my other vendors are now exposed, and must I act today? Vendor Risk Radar turns the live web into continuous, cited vendor risk intelligence. For each vendor it runs real-time discovery across Google News, breach trackers, CVE feeds, status pages and regulatory portals, extracts structured risk signals with AI, and computes a transparent 0–100 risk score with recency decay - every signal backed by a real source URL, never invented. Our differentiator, Blast Radius, reads recent security incidents across all vendors, automatically discovers the connections between them (shared attacker, OAuth token, identity provider, cross-vendor mention), and clusters them into single incidents. For each it issues a clear verdict—INVESTIGATE / MONITOR / NO ACTION - with reasoning and citations, correctly separating the 4-vendor Salesloft-Drift OAuth cascade from the Okta–Cloudflare identity incident. Built with Bright Data SERP API for live discovery and Web Unlocker to bypass bot-protected breach trackers and trust centers (provable 403→200), plus AI/ML API (Claude) for extraction. A hosted MCP server exposes the data to any AI agent—just ask "Am I exposed to a cascading breach this week?" The stack (FastAPI + React + SQLite) is containerized and deployed live on Hugging Face Spaces, moving third-party risk from reactive headlines to proactive, connection-aware monitoring.