What's New 2025 Q4

Debugging Assistant

The all new Fiddler Debugging Assistant lets you chat with your preferred LLM directly inside the tool, helping you debug traffic faster with real-time insights and smart suggestions. 

• Get instant answers to common debugging questions. The assistant helps you interpret traffic, identify issues, and suggests best practices to resolve problems quickly.
  
• Learn how to make the most of Fiddler Everywhere. Ask about features, settings, and workflows, and receive clear guidance to optimise your debugging experience.
  
• Dive deep into individual sessions. The assistant provides real-time insights, explains anomalies, and offers tailored suggestions to fix issues faster.

The Fiddler Debugging Assistant streamlines your processes and allows you to be even more productive.

Fiddler MCP Integration

The Fiddler MCP (Model Context Protocol) integration is specifically designed to make Fiddler Everywhere’s powerful debugging and traffic-inspection data accessible to AI assistants, right where developers work. This ensures you can identify, analyze and resolve issues faster, without even leaving your favourite IDE. It’s like having an extra team member who:

• Talks your language, turning debugging into a conversation. Need to find sessions that are taking too long? Just ask.
  
  
• Debugs during development, helping you identify and resolve issues before they reach testing or production.
  
  
• Keeps your data secure, automatically sanitizing sensitive information before anything is shared with the model.
  

Network Adapter on Windows

Now available on Windows, Network Capture Mode lets you intercept all traffic flowing through your machine - regardless of proxy settings. Capture traffic from any app or process, even those that don’t respect system proxies.  

Reverse Proxy

The Reverse Proxy feature in Fiddler Everywhere enables targeted inspection and debugging of HTTP(S) traffic to local or remote servers. It captures requests from clients to a specific server, such as a local IIS instance or a remote API endpoint, for precise server-side analysis. Set the client port and target server in Fiddler Everywhere to debug server behavior with ease. 

Add Sessions to Snapshots

Compare traffic across captures, build a fuller picture of an issue, or keep everything neatly in one place. You can now add new sessions with ease — from Live Traffic to an existing snapshot or from one snapshot to another. 

Custom Certificate Support

Enterprise companies can now use a custom certificate to encrypt HTTPS traffic.  Through managed app configurations, admins can control how certificates are distributed, trusted, and maintained at scale.  

Detect Cisco VPN

Fiddler Everywhere now automatically detects and bypasses Cisco’s global URL to prevent conflicts that block traffic capture. This reduces the need for manual setup as everything is being handled by the app on startup.