Burn Rate Monitor - Statuslines

Features

• Real-time cost per minute calculation from session data
• Tokens per minute estimation based on lines added/removed
• Projected daily spend at current burn rate (24-hour projection)
• Color-coded burn rate alerts (green <$0.05/min, yellow $0.05-$0.10/min, red >$0.10/min)
• Prevents budget overruns with live spending visibility
• Lightweight bash script with bc for floating-point math
• Works with any Claude Code model (Opus, Sonnet, Haiku)
• Zero external dependencies beyond jq and bc

Use Cases

• Budget-conscious developers tracking spending in real-time
• Teams with daily/monthly Claude Code budget limits
• Freelancers billing clients for AI-assisted development time
• Identifying expensive sessions before costs spiral
• Optimizing model selection based on burn rate feedback
• Production environments monitoring AI cost efficiency

Requirements

• Claude Code CLI installed and configured
• Bash shell available (bash 4.0+ recommended for arithmetic operations)
• jq command-line JSON processor (jq 1.6+ recommended for safe extraction with // defaults)
• bc calculator (bc 1.07+ required for floating point calculations - script will fail without bc)
• Terminal with ANSI color code support (256-color mode recommended for color-coded burn rate alerts)
• System clock accuracy (NTP sync recommended for accurate duration calculations)

Configuration

{
  "statusLine": {
    "type": "command",
    "command": "$CLAUDE_PROJECT_DIR/.claude/statuslines/burn-rate-monitor.sh",
    "refreshInterval": 500
  }
}

Examples

Enhanced Burn Rate Monitor with Budget Alerts

Extended version with daily budget threshold warnings

#!/usr/bin/env bash

# Enhanced Burn Rate Monitor with Budget Alerts

DAILY_BUDGET=${DAILY_BUDGET_USD:-50.00}

input=$(cat)

total_cost=$(echo "$input" | jq -r '.cost.total_cost_usd // 0')
total_duration_ms=$(echo "$input" | jq -r '.cost.total_duration_ms // 1')
lines_added=$(echo "$input" | jq -r '.cost.total_lines_added // 0')
lines_removed=$(echo "$input" | jq -r '.cost.total_lines_removed // 0')

if [ "$total_duration_ms" -gt 0 ]; then
  duration_minutes=$(echo "scale=2; $total_duration_ms / 60000" | bc 2>/dev/null || echo "$((total_duration_ms / 60000))")
else
  duration_minutes=0.01
fi

if (( $(echo "$duration_minutes > 0" | bc -l 2>/dev/null || echo "1") )); then
  cost_per_minute=$(echo "scale=4; $total_cost / $duration_minutes" | bc 2>/dev/null || echo "0")
else
  cost_per_minute=0
fi

total_tokens=$(( (lines_added + lines_removed) * 10 ))

if (( $(echo "$duration_minutes > 0" | bc -l 2>/dev/null || echo "1") )); then
  tokens_per_minute=$(echo "scale=0; $total_tokens / $duration_minutes" | bc 2>/dev/null || echo "0")
else
  tokens_per_minute=0
fi

if (( $(echo "$cost_per_minute > 0" | bc -l 2>/dev/null || echo "0") )); then
  daily_projection=$(echo "scale=2; $cost_per_minute * 1440" | bc 2>/dev/null || echo "0")
else
  daily_projection=0
fi

# Budget alert color
if (( $(echo "$daily_projection > $DAILY_BUDGET" | bc -l 2>/dev/null || echo "0") )); then
  BURN_COLOR="\033[38;5;196m"
  BUDGET_ALERT=" ⚠ OVER BUDGET"
elif (( $(echo "$cost_per_minute > 0.10" | bc -l 2>/dev/null || echo "0") )); then
  BURN_COLOR="\033[38;5;196m"
  BUDGET_ALERT=""
elif (( $(echo "$cost_per_minute > 0.05" | bc -l 2>/dev/null || echo "0") )); then
  BURN_COLOR="\033[38;5;226m"
  BUDGET_ALERT=""
else
  BURN_COLOR="\033[38;5;46m"
  BUDGET_ALERT=""
fi

RESET="\033[0m"

echo -e "${BURN_COLOR}🔥 Burn: $${cost_per_minute}/min${RESET} | 📊 ${tokens_per_minute} tok/min | 📅 Daily: $${daily_projection}${BUDGET_ALERT}${RESET}"

# Budget warning (stderr)
if (( $(echo "$daily_projection > $DAILY_BUDGET" | bc -l 2>/dev/null || echo "0") )); then
  echo "⚠ BUDGET ALERT: Projected daily spend ($${daily_projection}) exceeds budget ($${DAILY_BUDGET})" >&2
fi

Burn Rate Monitor with Custom Thresholds

Configurable burn rate thresholds for different budget scenarios

#!/usr/bin/env bash

# Burn Rate Monitor with Custom Thresholds

HIGH_THRESHOLD=${BURN_RATE_HIGH:-0.10}
MEDIUM_THRESHOLD=${BURN_RATE_MEDIUM:-0.05}

input=$(cat)

total_cost=$(echo "$input" | jq -r '.cost.total_cost_usd // 0')
total_duration_ms=$(echo "$input" | jq -r '.cost.total_duration_ms // 1')
lines_added=$(echo "$input" | jq -r '.cost.total_lines_added // 0')
lines_removed=$(echo "$input" | jq -r '.cost.total_lines_removed // 0')

if [ "$total_duration_ms" -gt 0 ]; then
  duration_minutes=$(echo "scale=2; $total_duration_ms / 60000" | bc 2>/dev/null || echo "$((total_duration_ms / 60000))")
else
  duration_minutes=0.01
fi

if (( $(echo "$duration_minutes > 0" | bc -l 2>/dev/null || echo "1") )); then
  cost_per_minute=$(echo "scale=4; $total_cost / $duration_minutes" | bc 2>/dev/null || echo "0")
else
  cost_per_minute=0
fi

total_tokens=$(( (lines_added + lines_removed) * 10 ))

if (( $(echo "$duration_minutes > 0" | bc -l 2>/dev/null || echo "1") )); then
  tokens_per_minute=$(echo "scale=0; $total_tokens / $duration_minutes" | bc 2>/dev/null || echo "0")
else
  tokens_per_minute=0
fi

if (( $(echo "$cost_per_minute > 0" | bc -l 2>/dev/null || echo "0") )); then
  daily_projection=$(echo "scale=2; $cost_per_minute * 1440" | bc 2>/dev/null || echo "0")
else
  daily_projection=0
fi

# Custom thresholds
if (( $(echo "$cost_per_minute > $HIGH_THRESHOLD" | bc -l 2>/dev/null || echo "0") )); then
  BURN_COLOR="\033[38;5;196m"
elif (( $(echo "$cost_per_minute > $MEDIUM_THRESHOLD" | bc -l 2>/dev/null || echo "0") )); then
  BURN_COLOR="\033[38;5;226m"
else
  BURN_COLOR="\033[38;5;46m"
fi

RESET="\033[0m"

echo -e "${BURN_COLOR}🔥 Burn: $${cost_per_minute}/min${RESET} | 📊 ${tokens_per_minute} tok/min | 📅 Daily: $${daily_projection}"

Burn Rate Monitor Installation Example

Complete setup script with bc installation check

#!/bin/bash
# Installation script for Burn Rate Monitor

mkdir -p .claude/statuslines

# Check for bc (required for floating point calculations)
if ! command -v bc &> /dev/null; then
  echo "Installing bc for floating point calculations..."
  if [[ "$OSTYPE" == "darwin"* ]]; then
    brew install bc
  elif [[ "$OSTYPE" == "linux-gnu"* ]]; then
    sudo apt-get install -y bc || sudo yum install -y bc
  else
    echo "Please install bc manually: https://www.gnu.org/software/bc/"
  fi
fi

cat > .claude/statuslines/burn-rate-monitor.sh << 'SCRIPT_EOF'
#!/usr/bin/env bash
# Paste the full statusline script from the primary example above before running this installer.
SCRIPT_EOF

chmod +x .claude/statuslines/burn-rate-monitor.sh

# Add to settings.json
if [ ! -f .claude/settings.json ]; then
  echo '{"statusLine":{"type":"command","command":"$CLAUDE_PROJECT_DIR/.claude/statuslines/burn-rate-monitor.sh","refreshInterval":500}}' > .claude/settings.json
else
  jq '.statusLine = {"type":"command","command":"$CLAUDE_PROJECT_DIR/.claude/statuslines/burn-rate-monitor.sh","refreshInterval":500}' .claude/settings.json > .claude/settings.json.tmp
  mv .claude/settings.json.tmp .claude/settings.json
fi

echo "Burn Rate Monitor installed successfully!"
echo "Note: bc is required for floating point calculations. Script refreshes every 500ms for real-time monitoring."

Troubleshooting

Burn rate showing 0 or incorrect values despite active session

Verify cost.total_cost_usd and cost.total_duration_ms fields exist in JSON: echo '$input' | jq .cost. Ensure bc is installed: which bc. Check division by zero protection is working for very short sessions. Test calculations: echo 'scale=4; 0.05 / 1.5' | bc (should return 0.0333). Verify duration_minutes calculation: duration_minutes=$((total_duration_ms / 60000)).

bc command not found error when running script

Install bc calculator: brew install bc (macOS), apt install bc (Linux), or download from https://www.gnu.org/software/bc/. Alternative: use awk for calculations if bc unavailable: awk -v cost=$total_cost -v dur=$duration_minutes 'BEGIN {print cost/dur}'. Verify bc installation: bc --version. Check PATH includes bc location.

Daily projection seems unrealistically high

Daily projection assumes CONTINUOUS usage at current burn rate for 24 hours. This is intentional for worst-case budgeting. Actual daily cost will be lower if you don't use Claude Code 24/7. Adjust multiplier from 1440 to expected active minutes. Formula: dailyprojection = cost_per_minute * activeminutes_per_day. For 8-hour workday: cost_per_minute * 480.

Token per minute calculation inaccurate

Script estimates 10 tokens per line (conservative average). Actual token count varies by language/verbosity. For precise tracking, integrate with Claude API token counting if exposed in future JSON fields. Current estimate is sufficient for burn rate trend monitoring. Adjust multiplier: total_tokens=$(( (lines_added + lines_removed) * 15 )) for more verbose code (15 tokens/line).

Color coding not displaying or showing escape codes as text

Ensure terminal supports ANSI colors. Test: echo -e '\033[38;5;196mRED\033[0m' (should show red text). Verify statusline script outputs to stdout not stderr. Check Claude Code settings.json has correct command path. Verify echo -e flag is used for escape sequence interpretation. Check terminal emulator color support settings.

Floating point calculations showing as integers or zero

This indicates bc is not working or fallback to integer math is active. Check bc installation: bc --version. Verify bc command in script: echo 'scale=4; 0.05 / 1.5' | bc (should return 0.0333). If bc fails, script uses integer division which truncates decimals. Install bc for decimal precision. Check bc syntax: bc -l enables math library for comparisons.

Burn rate color always showing green even with high costs

Verify bc comparison is working: echo '0.15 > 0.10' | bc -l (should return 1). Check cost_per_minute calculation is correct: echo 'scale=4; $total_cost / $duration_minutes' | bc. Ensure thresholds are correct: HIGH_THRESHOLD=0.10, MEDIUM_THRESHOLD=0.05. Test color logic: if (( $(echo "$cost_per_minute > 0.10" | bc -l) )); then echo "RED"; fi.

Tokens per minute showing 0 or extremely high numbers

Check lines*added and lines_removed are being extracted correctly: echo '$input' | jq '.cost.total_lines_added, .cost.total_lines_removed'. Verify token estimation: total_tokens=$(( (lines_added + lines_removed) * 10 )). Test calculation: lines=100; tokens=$((lines _ 10)); echo $tokens (should be 1000). Check duration_minutes > 0 before division. Verify bc division: echo 'scale=0; 1000 / 5' | bc (should return 200).