Accessing a Remote Project with LangSmith Studio

langchain langstudio langgraph llm network Reverse-Proxy apache https

This article is intended for developers using LangChain or LangGraph who run their projects on a remote server and want to access them through LangSmith Studio without setting up a local development environment.

When working in teams or using server-side resources (such as local LLMs), accessing LangSmith Studio can become challenging due to networking and browser security constraints. This guide explains the problem and presents reliable solutions.

Problem Overview

When developing a LangChain or LangGraph project locally, LangSmith Studio can be accessed using a URL similar to the following:

https://smith.langchain.com/studio/?baseUrl=http://127.0.0.1:2024

This works because LangSmith Studio communicates with a locally running API server.

However, this approach has an important limitation.

Why the Default Studio URL Fails for Teams

The 127.0.0.1 (localhost) address refers to the user’s own machine, not the remote server.
As a result:

  • Each developer must pull the project locally
  • Each developer must run the API server on their own machine
  • The Studio link does not work for team members who do not have the project running locally

This becomes impractical or impossible when:

  • The project relies on server-only resources
  • A local model (e.g., Ollama) runs exclusively on the remote machine
  • You want a single shared debugging environment

Accessing a Remote LangGraph Server

In theory, LangSmith Studio can connect to a remote server by pointing baseUrl to a public IP address:

https://smith.langchain.com/studio/?baseUrl=http://SERVER_IP:2024

Prerequisites

Before proceeding, ensure that:

  • SERVER_IP:2024 is publicly accessible (NAT / port forwarding configured if needed)
  • LangGraph is started with a public host binding: 
    --host SERVER_IP
  • The API server is running correctly

You can verify access with:

curl http://SERVER_IP:2024

If the configuration is correct, the server should respond with "Not Found" or you should be able to access:

http://SERVER_IP:2024/docs

Common Browser Error: Mixed Content

When opening the Studio link in the browser, you may see the following error:

Failed to initialize Studio
Please verify if the API server is running or accessible from the browser.
TypeError: NetworkError when attempting to fetch resource.

In the browser console, you may notice an error similar to:

mixed content loading blocked

What Is Happening?

LangSmith Studio is served over HTTPS, but it attempts to communicate with an HTTP API server.

Modern browsers block this behavior because secure (HTTPS) pages are not allowed to load resources over insecure (HTTP) connections. This is known as a Mixed Content restriction.

Solution 1: Local Proxy (Not Recommended)

One workaround is to proxy the remote server through the developer’s local machine:

localhost → proxy → remote server

For example:

http://127.0.0.1:2024/assistants/search

is forwarded to:

http://SERVER_IP:2024/assistants/search

Drawbacks

  • Every developer must configure a proxy
  • Adds setup overhead
  • Not scalable for teams

⚠️ This approach is generally unsuitable for collaborative or production environments.

Solution 2: HTTPS Access via Domain (Recommended)

✅ Recommended approach

The most reliable and scalable solution is to expose the API server via a domain name secured with HTTPS.

High-Level Idea

  1. Assign a domain or subdomain to your server
  2. Enable HTTPS using a reverse proxy (e.g., Apache or Nginx)
  3. Forward HTTPS traffic to the internal LangGraph server

Your Studio URL becomes:

https://smith.langchain.com/studio/?baseUrl=https://SUBDOMAIN.YOUR_DOMAIN

Enabling HTTPS with Certbot (Apache Example)

You can obtain a free TLS certificate using Certbot:

sudo certbot --apache

Example Apache Configuration

<IfModule mod_ssl.c>
<VirtualHost *:443>
    ProxyPreserveHost On
    ServerName SUBDOMAIN.YOUR_DOMAIN

    ProxyPass / http://SERVER_IP:2024/
    ProxyPassReverse / http://SERVER_IP:2024/

    RewriteEngine on

    SSLCertificateFile /etc/letsencrypt/live/SUBDOMAIN.YOUR_DOMAIN/fullchain.pem
    SSLCertificateKeyFile /etc/letsencrypt/live/SUBDOMAIN.YOUR_DOMAIN/privkey.pem
    Include /etc/letsencrypt/options-ssl-apache.conf
</VirtualHost>
</IfModule>

After this setup, LangSmith Studio can securely communicate with the remote server without browser restrictions.

Final Result

You can now access your remote project using:

https://smith.langchain.com/studio/?baseUrl=https://SUBDOMAIN.YOUR_DOMAIN
flowchart TD A[LangSmith Studio Browser] subgraph Proxy Solution A -->|127.0.0.1:2024 Proxy| C[Local Proxy] C end subgraph HTTPS Solution E["Server: LangGraph / LangChain API"] A -->|https://subdomain.domain| D[Apache / Nginx Reverse Proxy] D end E D -->|"HTTP"| E C -->|"HTTP"| E A -->|"HTTPS over static IP"| E E F["Project Access & Debugging"] E --> F

This configuration allows:

  • Secure HTTPS communication
  • A shared debugging environment
  • Zero local setup for team members
  • Compatibility with browser security policies

Conclusion

By exposing your LangGraph or LangChain server through an HTTPS-secured domain, you eliminate Mixed Content issues and enable seamless access to LangSmith Studio for your entire team. This approach is ideal for production systems, collaborative development, and server-only model deployments.

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