Watch Your Claude Code Context Turn Into a Growing Black Hole in the Terminal

When browsing X, the author saw an animated GIF of a black hole drifting in the Ghostty terminal, gradually enlarging and swallowing on‑screen text. The black hole’s appetite represents Claude Code’s context window: as the conversation approaches its limit, Claude automatically compacts, causing earlier project details to fade.

The open‑source project ghostty-blackhole implements this visual metaphor as a Ghostty terminal plugin. Ghostty is a popular open‑source terminal with over 50 k stars on GitHub, and since version 1.0 it offers a custom shader interface that lets users write GLSL code to process the terminal display. The plugin uses this interface to render a real‑time, ray‑traced black hole, inspired by Eric Bruneton’s black‑hole shader that combines pre‑computed lookup tables with ray tracing.

Every frame and pixel is computed on the GPU, so the black hole’s appearance emerges from physical formulas rather than being hand‑drawn. As the Claude Code context fills, the black hole grows from a tiny speck (≈0.06 % of screen area) in the upper‑right corner to eventually covering the whole screen when the context is full, visibly distorting nearby text into “spaghetti”‑like shapes.

Ghostty Blackhole puts a real, ray‑traced black hole inside your terminal. It grows as Claude Code's context window fills up, live.

The visual effect is not a static overlay; the photon ring, accretion disc, and gravitational lensing are all computed on the GPU, making the black hole’s size directly reflect the amount of context stored.

Installation and usage :

Clone the repository:

git clone https://github.com/s0xDk/ghostty-blackhole

Add the shader to Ghostty’s configuration (macOS path: ~/Library/Application Support/com.mitchellh.ghostty/config)

custom-shader = /path/to/blackhole.glsl
custom-shader-animation = true

Integrate the claude-token.py script with Claude Code by editing ~/.claude/settings.json to add a statusLine command and hooks for SessionStart and SessionEnd that invoke the script.

Reload Ghostty (cmd+shift+, on macOS) or open a new window; the black hole appears as a tiny dot in the corner.

Start a new Claude Code session; the cursor turns amber and the black hole expands as the context grows. When the context reaches 100 %, the black hole can consume the entire screen. Running /compact or starting a new session instantly shrinks the black hole back to a normal terminal.

By following these steps, users can visually monitor Claude Code’s context consumption directly within their terminal.