Custom Status Line for Claude Code

· 2 min read ·
·
Claude Code CLI Bash

Today I discovered Claude Code supports custom status lines through a simple bash script.

After squinting at the default status bar one too many times, I built one that shows everything I actually care about - git context and token burn rate - in a single glanceable line.

The Problem

Claude Code’s default status line is functional but minimal.

When you’re deep in a refactoring session, you want to know:

  • What branch am I on?
  • How many lines have I changed?
  • How much context window do I have left?
  • Am I burning through tokens?

The Solution

Claude Code pipes JSON to your status line script via stdin. You parse it with jq, grab git info, calculate padding, and output a single line with left/right alignment.

#!/bin/bash
input=$(cat)

# Parse JSON from Claude Code
dir=$(echo "$input" | jq -r '.workspace.current_dir')
model=$(echo "$input" | jq -r '.model.display_name // .model.id')
total_input=$(echo "$input" | jq -r '.context_window.total_input_tokens // 0')

# Git info
branch=$(git -c core.useBuiltinFSMonitor=false branch --show-current 2>/dev/null)
diff_stats=$(git diff --shortstat 2>/dev/null)

# Terminal width for right-alignment
term_width=${COLUMNS:-$(stty size 2>/dev/null | cut -d' ' -f2)}
[ -z "$term_width" ] && term_width=120

# Calculate padding between left and right sections
padding=$((term_width - left_len - right_len))
printf '%b%*s%b' "$left" "$padding" "" "$right"

The full script handles context window percentage (color-coded: green >50%, yellow >20%, red otherwise), session duration, and token formatting with k suffixes.

Full script on GitHub Gist

Configuration

Add to ~/.claude/settings.json:

{
  "statusLine": {
    "type": "command",
    "command": "/Users/<you>/.claude/statusline-command.sh"
  }
}

What It Shows

Left SideRight Side
Directory nameModel name
Git branchSession duration
Lines added/removedContext window % left
Token in/out counts

The output adapts to terminal width:

Custom status line showing git branch on the left, model and token metrics on the right

What I Learned

  • Claude Code exposes rich JSON data to status line scripts: workspace, model, tokens, context window usage
  • tput cols doesn’t work in piped contexts - use $COLUMNS or stty size instead
  • Unicode characters (│, ↓) break ${#var} length calculations - use wc -m for visible width
  • The core.useBuiltinFSMonitor=false flag prevents git from hanging on optional locks

References

Customizing your Claude Code setup? I’d love to see what status lines others have built. Reach out on LinkedIn.