Anti-Crash Sanitizer

Even the most advanced LLMs can make small syntax mistakes when generating complex Manim code. MovingLines includes a multi-layered Sanitization Engine that scans and repairs code before it ever reaches the renderer.

Why do we need it?

Manim CE is strict. A single extra comma or a mismatched vector dimension will crash the entire scene. Our sanitizer acts as a "hardened" buffer to ensure high success rates.

Core Sanitization Rules

1. Vector-to-Scalar Fixes

A common hallucination is passing a coordinate (Vector) into a method that expects a single float (Scalar).

• HALLUCINATION: obj.set_x(RIGHT * 3)
• FIX: obj.set_x(3)

2. Method Hook Hallucinations

LLMs often hallucinate parameters that existed in older versions of Manim or don't exist at all.

• add_tip: Fixes invalid at_arg or at_start parameters.
• ArcBetweenPoints: Automatically converts start_point/end_point to the correct start/end.
• BezierCurve: Automatically converts the non-standard BezierCurve class to CubicBezier.

3. Indentation Normalization

The most common cause of IndentationError in Python. Our engine:

• Snaps all indents to 4-space boundaries.
• Removes mixed tabs/spaces.
• Validates the code structure using Python's compile() function before finalizing.

4. 3D Camera Protection

Prevents crashes in ThreeDScene by removing invalid .animate calls on the camera object, which is a frequent AI mistake.

Self-Healing Loop

If the renderer still fails after sanitization, MovingLines triggers a Self-Healing Loop:

1. The error log is sent back to the LLM.
2. The LLM is asked to "self-correct" based on the traceback.
3. The new code is sanitized and re-rendered.

This double-check system significantly increases the reliability of the platform.