claude-code-statusline-development - SKILL.md Agent Skill

name: claude-code-statusline-development description: This skill should be used when the user asks to "create a statusline", "customize the status line", "add a custom prompt", or mentions Claude Code statusline. Also suggest when the user wants to display git branch, context usage, model name, or session costs at the bottom of Claude Code. allowed-tools: Read, Grep

Claude Code Statusline Development

Create custom status lines that display contextual information at the bottom of Claude Code.

Quick Reference

You MUST read the reference files for detailed schemas and examples:

JSON Schema - Complete input structure documentation
Example: Simple - Basic bash statusline
Example: Git-Aware - Git branch and status
Example: Context Usage - Context window percentage
Example: Cost Tracking - Session costs and tokens

Configuration

Add to .claude/settings.json:

{
  "statusLine": {
    "type": "command",
    "command": "~/.claude/statusline.sh",
    "padding": 0
  }
}

How It Works

Status line updates when conversation messages change
Updates run at most every 300ms
First line of stdout becomes the status line text
ANSI color codes supported
JSON context passed via stdin

JSON Input (Quick Reference)

Field	Description
`model.display_name`	Model name (e.g., "Opus")
`workspace.current_dir`	Current working directory
`workspace.project_dir`	Original project directory
`cost.total_cost_usd`	Session cost in USD
`cost.total_lines_added`	Lines added this session
`cost.total_lines_removed`	Lines removed this session
`context_window.context_window_size`	Max context tokens
`context_window.current_usage`	Current token usage object

See JSON Schema for complete structure.

Script Template

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

# Extract values using jq
model=$(echo "$input" | jq -r '.model.display_name')
dir=$(echo "$input" | jq -r '.workspace.current_dir')

# Colors via tput
blue=$(tput setaf 4)
reset=$(tput sgr0)

echo "${blue}[$model]${reset} ${dir##*/}"

Make executable:

chmod +x ~/.claude/statusline.sh

Tips

Keep output concise - single line only
Use tput for portable ANSI colors
Test with mock JSON: echo '{"model":{"display_name":"Test"}}' | ./statusline.sh
Cache expensive operations (git status) if needed

Important

After creating or modifying statuslines, inform the user:

No restart needed. Statusline changes take effect immediately - Claude Code reads settings fresh on each update.

Attribution

Based on Claude Code Status Line Configuration.