Why Claude Code output pastes messy — and how to fix it

Claude Code runs in a terminal. Terminals draw text using a mix of characters, ANSI escape codes, and Unicode glyphs to produce the polished UI you see — line numbers, color highlighting, frames, and tool-call markers. None of those visual aids exist in the underlying text; they're drawn around it.

But when you select-and-copy from a terminal, your clipboard captures the rendered text — meaning the line numbers and frame characters come along as actual characters. Pasting that into VS Code or your IDE is when the mess shows up.

• Line-number prefixes like 1\t, 42│ from the Read tool's cat -n format.
• ANSI escape codes like \x1B[33m for syntax highlighting that your editor renders as garbage.
• Box-drawing characters like ─ │ ┌ ┐ └ ┘ from tool-call frames.
• Bullet markers like ●, ⏺ that prefix tool calls and assistant turns.
• Indentation padding from the UI that becomes a multi-space leading indent on every line.
• Soft-wrap line breaks the terminal added at your window width, which split sentences that were originally one line.

The dumb fix: select carefully, manually delete line numbers, run a regex find-replace, hand-fix indentation. Loses you 30 seconds and your patience every time.

The smart fix: paste into the cleaner on the homepage and copy the output. Each transform is a separate toggle so you stay in control: keep diff markers when you want them, drop indentation when it's padding rather than structure.

1. Normalises line endings to LF.
2. Strips ANSI escape sequences.
3. Removes Unicode box-drawing and arrow glyphs.
4. Drops line-number prefixes (tab- and pipe-delimited).
5. Strips tool-call bullet markers.
6. Optionally removes diff +/- markers.
7. Trims trailing whitespace per line.
8. Detects and removes the common leading indent.
9. Optionally rejoins soft-wrapped paragraphs.
10. Collapses runs of blank lines.

Code snippets often contain tokens, internal hostnames, or proprietary logic. Sending them to a third-party server to clean whitespace is overkill at best and a security policy violation at worst. Every transform here runs in your browser via plain JavaScript — open DevTools and verify there are no network calls.