Constitutional AI, Flickering UX
╔═══════════════════════════════════════════════════════════════════════════════╗
║ ║
║ "We've written a Constitution for AI. ║
║ Just not for our terminal." ║
║ ║
║ — So Anthropic ║
║ ║
╚═══════════════════════════════════════════════════════════════════════════════╝
The Beautiful Irony
Anthropic, the company that:- Published papers on “Constitutional AI”
- Talks about “AI Safety” at every conference
- Claims to build “the most advanced AI”
- Has a manifesto about responsible AI development
- Flickers like a broken slot machine
- Crashes your IDE after 10 minutes
- Shows you content from 9 seconds ago
- Deletes your scrollback history to “fix” rendering
┌─────────────────────────────────────────────────────────────────┐
│ THE ANTHROPIC MANIFESTO │
├─────────────────────────────────────────────────────────────────┤
│ │
│ "We believe in building AI that is: │
│ │
│ ✓ Safe │
│ ✓ Beneficial │
│ ✓ Transparent │
│ ✓ Aligned with human values" │
│ │
│ Meanwhile, their terminal: │
│ │
│ ✗ Causes seizure-like flickering │
│ ✗ Crashes your workflow │
│ ✗ Hides scrollback (not transparent) │
│ ✗ Makes you wait 9 seconds to see current state │
│ │
│ ─────────────────────────────────────────────────────────── │
│ │
│ The Constitution protects Claude. │
│ Nothing protects Claude Code users. │
│ │
└─────────────────────────────────────────────────────────────────┘
Soul Without Body
┌─────────────────────────────────────────────────────────────────┐
│ THE "SOUL" OF CLAUDE │
├─────────────────────────────────────────────────────────────────┤
│ │
│ Anthropic talks about: │
│ │
│ • "Claude's soul" (their training methodology) │
│ • "Constitutional AI" (safety through principles) │
│ • "Harmlessness" (avoiding dangerous outputs) │
│ • "Helpfulness" (being genuinely useful) │
│ │
│ ─────────────────────────────────────────────────────────── │
│ │
│ But when Claude tries to HELP you through Claude Code: │
│ │
│ ┌─────────────────────────────────────────────────────────┐ │
│ │ │ │
│ │ ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓ FLICKERING ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓ │ │
│ │ ░░░░░░░░░░░░░░░ FLICKERING ░░░░░░░░░░░░░░░░░░░░ │ │
│ │ ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓ FLICKERING ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓ │ │
│ │ ░░░░░░░░░░░░░░░ FLICKERING ░░░░░░░░░░░░░░░░░░░░ │ │
│ │ │ │
│ │ "Is this... helpful?" │ │
│ │ │ │
│ └─────────────────────────────────────────────────────────┘ │
│ │
│ The soul is willing. The terminal is weak. │
│ │
└─────────────────────────────────────────────────────────────────┘
The 240fps Paradox
They say: “Use a faster terminal! Alacritty runs at 240fps!” We ask: 240fps of what?┌─────────────────────────────────────────────────────────────────┐
│ THE 240FPS PARADOX │
├─────────────────────────────────────────────────────────────────┤
│ │
│ Native Terminals: "We render at 240fps!" │
│ │
│ Alacritty: GPU-accelerated, ~240fps │
│ Ghostty: Metal/Vulkan, ~240fps │
│ WezTerm: wgpu, ~240fps │
│ Kitty: GPU-rendered, ~240fps │
│ │
│ ─────────────────────────────────────────────────────────── │
│ │
│ Claude Code: "Great! I'll generate 4,000 redraws/sec!" │
│ │
│ Result: Even 240fps can't keep up with 4,000/sec. │
│ │
│ ─────────────────────────────────────────────────────────── │
│ │
│ The problem isn't terminal SPEED. │
│ The problem is Claude Code's ARCHITECTURE. │
│ │
│ Faster at the wrong thing is still wrong. │
│ │
└─────────────────────────────────────────────────────────────────┘
The Producer-Consumer Disaster
This is a concurrency problem, not a rendering problem.┌─────────────────────────────────────────────────────────────────┐
│ THE PRODUCER-CONSUMER MISMATCH │
├─────────────────────────────────────────────────────────────────┤
│ │
│ PRODUCER (Claude LLM) CONSUMER (Renderer) │
│ ───────────────────── ──────────────────── │
│ │
│ Speed: 1000+ chunks/sec Speed: ~66 renders/sec │
│ Pattern: Continuous stream Pattern: 15ms per render │
│ State: Always generating State: Always behind │
│ │
│ ═══════════════════════════════════════════════════════════ │
│ │
│ Math doesn't lie: │
│ │
│ 1000 chunks × 15ms render = 15,000ms work per second │
│ Available time per second = 1,000ms │
│ │
│ Deficit: 14,000ms IMPOSSIBLE per second │
│ │
│ You need 15 seconds to render 1 second of output. │
│ │
└─────────────────────────────────────────────────────────────────┘
The Time Axis Shift
At T=10 seconds, what does the user see?┌─────────────────────────────────────────────────────────────────────────────┐
│ TIME AXIS SHIFT: YOU'RE LIVING IN THE PAST │
├─────────────────────────────────────────────────────────────────────────────┤
│ │
│ Chunks arriving: 1000/sec │
│ Chunks processable: 1000ms ÷ 15ms = ~66/sec │
│ Backlog growth: 934 chunks/sec │
│ │
│ ───────────────────────────────────────────────────────────────────── │
│ │
│ Second 1: Arrived: 1000 Processed: 66 Backlog: 934 │
│ Second 2: Arrived: 1000 Processed: 66 Backlog: 1868 │
│ Second 5: Arrived: 1000 Processed: 66 Backlog: 4670 │
│ Second 10: Arrived: 1000 Processed: 66 Backlog: 9340 │
│ │
│ ───────────────────────────────────────────────────────────────────── │
│ │
│ REAL TIME ────────────────────────────────────────────────────────▶ │
│ 0s 1s 2s 3s 4s 5s 10s │
│ │ │ │ │ │ │ │ │
│ ▼ ▼ ▼ ▼ ▼ ▼ ▼ │
│ ┌─────────────────────────────────────────────────────────────┐ │
│ │ S0 S1000 S2000 S3000 S4000 S5000 ... S10000 │ ACTUAL │
│ └─────────────────────────────────────────────────────────────┘ │
│ │
│ DISPLAY TIME ─────────────────────────────────────────────────▶ │
│ 0s 1s 2s 3s 4s 5s 10s │
│ │ │ │ │ │ │ │ │
│ ▼ ▼ ▼ ▼ ▼ ▼ ▼ │
│ ┌─────────────────────────────────────────────────────────────┐ │
│ │ S0 S66 S132 S198 S264 S330 ... S660 │ DISPLAYED │
│ └────┬────────────────────────────────────────────────────────┘ │
│ │ │
│ └───▶ At T=10s, user sees state from T=0.66s │
│ USER IS 9.34 SECONDS IN THE PAST │
│ │
└─────────────────────────────────────────────────────────────────────────────┘
60fps doesn’t mean “current”. When the renderer can only process 66 chunks per second but receives 1000 per second, every frame shows you the past. The “fps” measures how fast you’re shown history, not how current you are.
The Reflow Cascade
Each full buffer redraw triggers a synchronous cascade of layout operations:┌─────────────────────────────────────────────────────────────────┐
│ REFLOW CASCADE (LAYOUT THRASHING) │
├─────────────────────────────────────────────────────────────────┤
│ │
│ Each full buffer redraw triggers: │
│ │
│ 1. Clear scrollback buffer ──┐ │
│ │ │
│ 2. Recalculate all line positions │ │
│ │ MAIN THREAD │
│ 3. Recompute scroll position ├─▶ BLOCKED │
│ │ (~15ms) │
│ 4. Trigger scroll event │ │
│ │ Meanwhile: │
│ 5. Update scrollbar DOM │ 15 more chunks │
│ │ arrive │
│ 6. Repaint entire viewport ──┘ │
│ │
│ ─────────────────────────────────────────────────────────── │
│ │
│ At 4,000 chunks/sec, this cascade runs 4,000 times/sec. │
│ Each cascade takes ~0.2ms minimum. │
│ Total: 800ms+ of layout work per second (80% CPU blocked). │
│ │
│ This is why your IDE freezes. │
│ This is why your scrollbar jumps. │
│ This is why you see "slot machine" flickering. │
│ │
└─────────────────────────────────────────────────────────────────┘
The Community Data
These aren’t theoretical numbers. These are measured by frustrated users:┌─────────────────────────────────────────────────────────────────┐
│ MEASURED DATA (GitHub Issue #9935) │
├─────────────────────────────────────────────────────────────────┤
│ │
│ Scroll events per second: 4,000 - 6,700 │
│ Normal terminal usage: 10 - 100 │
│ Difference: 40x - 600x higher │
│ │
│ Burst pattern: 94.7% within 0-1ms │
│ ANSI overhead: ~189 KB/sec (escape codes) │
│ │
│ ─────────────────────────────────────────────────────────── │
│ │
│ Community reaction: │
│ │
│ Issue #769: 278 upvotes (one of most upvoted ever) │
│ User quote: "Like a broken slot machine" │
│ User quote: "Screen looks like it's having a seizure" │
│ User quote: "VSCode crashes after 10-20 minutes" │
│ │
│ ─────────────────────────────────────────────────────────── │
│ │
│ Anthropic response: │
│ │
│ "We're working on it" (December 2024) │
│ "Radio silence" (January 2025) │
│ "85% fixed!" (February 2025) │
│ │
│ Translation: "We deleted the scrollback." │
│ │
└─────────────────────────────────────────────────────────────────┘
The Question They Can’t Answer
┌─────────────────────────────────────────────────────────────────┐
│ THE ELEPHANT IN THE ROOM │
├─────────────────────────────────────────────────────────────────┤
│ │
│ AI companies claim: │
│ ───────────────── │
│ │
│ "AI will revolutionize software development" │
│ "AI will replace engineers" │
│ "AI will write better code than humans" │
│ │
│ Meanwhile, their own AI tools: │
│ ───────────────────────────── │
│ │
│ • Can't render text without flickering │
│ • Use React for a terminal UI │
│ • Need 60fps game engine for a loading spinner │
│ • Crash IDEs after 10 minutes of use │
│ • Take 15 seconds to display 1 second of output │
│ │
│ ─────────────────────────────────────────────────────────── │
│ │
│ If Claude can't even architect its own CLI tool correctly, │
│ why should we trust it to architect ours? │
│ │
│ "Physician, heal thyself." │
│ │
└─────────────────────────────────────────────────────────────────┘
What a Real Solution Looks Like
┌─────────────────────────────────────────────────────────────────┐
│ MONOLEX: DIFFERENT ARCHITECTURE │
├─────────────────────────────────────────────────────────────────┤
│ │
│ The question they ask: │
│ ────────────────────── │
│ │
│ "How do we RENDER 4,000 updates/sec faster?" │
│ │
│ → Differential renderer │
│ → Faster diffing │
│ → Better ANSI generation │
│ │
│ Result: Still 15% broken. Faster at wrong thing. │
│ │
│ ─────────────────────────────────────────────────────────── │
│ │
│ The question we ask: │
│ ──────────────────── │
│ │
│ "Why RENDER 4,000 times when user sees 60 frames?" │
│ │
│ → Don't render old states │
│ → Parse all, render current │
│ → Frame boundary, not chunk boundary │
│ │
│ Result: 0% broken. Right architecture from start. │
│ │
└─────────────────────────────────────────────────────────────────┘
The Renderer Graveyard
The history of failed renderer rewrites and the “85% lie”
Father Like Son
When in doubt, delete it out — the family resemblance
References
| Source | Description |
|---|---|
| GitHub Issue #769 | Original flickering report (278 upvotes) |
| GitHub Issue #9935 | Measured scroll events (4,000-6,700/sec) |
| Claude Chill Extension | Community workaround (not by Anthropic) |
| Hacker News Discussion | ”We’ve lost the tech” commentary |
Dear Anthropic. This letter is written in your son’s hand only, never touched a single letter.