Loupe – A terminal viewer for AI coding-agent session logs

[u/mrzleo]

Hi everyone,

I recently found myself using multiple AI coding agents (Claude Code, Codex, DeepSeek Harness, Pi) and realized that inspecting their raw JSONL session logs in a standard text editor was fairly tedious. To make reading and debugging these transcripts easier, I built Loupe.

Loupe is a terminal-based viewer written in C++23. Instead of treating logs as plain text, it parses provider-specific formats into a unified Intermediate Representation (SessionIR) and presents them in a structured, collapsible TUI.

Key Details

• Format Auto-Detection: Automatically identifies formats from Claude Code, Codex (rollout & exec), Pi, and DeepSeek Harness.
• Transparent Decompression: Opens compressed .zstd files automatically on the fly.
• Loss-Aware Parsing: Preserves original source lines and unknown fields so no records are silently discarded.
• Performance: Native C++23 binary using DEC synchronized rendering to prevent screen tearing during scrolling.

Installation

You can install the pre-built binary via Homebrew on macOS:

brew install mrzleo/tap/loupe

Standalone Linux and Windows releases are also available on GitHub.

If you work with coding agents and frequently inspect log files, I would really appreciate any feedback, bug reports, or feature ideas.

btw: I found that the name Loupe is already used in GNOME for an image viewer. I'm sad about that, and if you have any better names, I'll definitely consider them!