Mediator vs NetworkSpy

Mediator is a free, open-source desktop proxy for debugging gRPC traffic on Linux, macOS and Windows. It can redirect requests to beta or test servers without changes to client code. When an API schema is available, it parses gRPC requests and responses and presents binary messages as a JSON tree. Schemas can come from server reflection, proto source roots compiled with protoc, or FileDescriptorSet files. Matching server rules also allow gRPC and HTTPS decoding after the client installs the root certificate generated by that Mediator installation. Certificates are available in DER and PEM formats, and another installation requires its own certificate. The proxy listens on port 8888 by default. Downloads include Windows MSI, macOS DMG, Apple Silicon macOS DMG and Linux deb packages. Setup examples cover Java, Objective-C/iOS and Go clients. The repository identifies Apache-2.0 as its license.

NetworkSpy is an application-level HTTP/HTTPS debugging tool for capturing and analyzing network traffic. It can intercept HTTPS, inspect request metadata, compare requests side by side, and let users edit and replay captured traffic. Breakpoints can pause or change live requests, and response mocking is supported. It also handles WebSocket message streaming and gRPC with Protobuf decoding. Its LLM analyzer visualizes streaming tokens, tracks token usage, and reports latency for each chunk; custom viewers can display proprietary binary formats or other structured data. NetworkSpy runs on macOS, Linux, and Windows, and physical iOS and Android devices can be configured to route traffic through it for inspection. The privacy policy says inspected traffic stays on the user's machine and is not collected or monitored. The free plan has limits on LLM token analysis and other features. Personal costs $18 a year, Professional $29 a year, Team Starter $49 a month, and Business $149 a month. An individual license is limited to one device.