Terminal-Based 3D Renderer Built with Multi-Agent Claude Code System

A developer built tortuise, a terminal-based 3D renderer that displays Gaussian splats using Unicode halfblock characters and ASCII symbols. The project was created over 3 days using a Claude Code setup with approximately 70-80 total agents across 3-4 sessions.

Agent Architecture

The Claude Code setup uses a specific pattern:

• Main session acts as coordinator, delegating tasks and communicating with the developer
• Task subagents can contain subagents inside them via agent-mux (skill and SDK→CLI wrappers)
• A "get shit done subagent" handles most work, capable of using Claude Code, Codex, and opencode agents internally

Development Workflow

The developer used several agent coordination strategies:

• Plan with Opus → challenge with Codex 5.3 xhigh → build with Codex-es 5.3 high → audit with Opus or Codex 5.3 xhigh
• For hard optimizations: Multiple Opus sessions with 4-5 Codex 5.3 xhigh agents in parallel researching orthogonal improvement approaches
• Self-verification loop using Peekaboo skill + toolset (macOS GUI automation) allowing agents to launch the terminal app on a headless Mac Mini and debug visually
• Context preservation between sessions via: .claude sessions JSON → deterministic markdown file → digest by Sonnet 4.6

Technical Details

tortuise is a TUI Gaussian Splats renderer with these characteristics:

• Renders .ply and .splat files in Unicode halfblock characters
• Handles 1M+ splats
• CPU-only rendering using Rust + Rayon
• Six render modes
• Runs over SSH
• Works on M2-M4 Apple Silicon

Challenges Encountered

The development faced several obstacles:

• Agents struggled to produce working Metal shaders for Gaussian Splats rendering, with neither Codex 5.3 xhigh nor Opus 4.6 succeeding
• Without proper code guidelines and modular design, agents tended to create "hacky monoliths" with "+5k lines of madness"
• Considerable work was spent on "common sense based polishing" like proper key mappings for movement and rotation

The project was inspired by Apple's open source SHARP model for image-to-3D scene conversion and the desire to create a GPU-free viewer for Gaussian splatting. The developer is continuing to add features, including a script to load 3D scenes from websites like SuperSplat.