Simple script to run claude headless without the -p (to avoid extra costs)

cs.sh

#!/usr/bin/env bash
# Usage: ./cs "your prompt"
# Runs Claude headlessly, suppresses the TUI, prints Claude's final reply on stdout.

set -uo pipefail

PROMPT="$*"
REPLY_FILE=$(mktemp)
SESSION_ID=$(uuidgen | tr 'A-Z' 'a-z')
ENC_CWD=$(pwd | sed 's|/|-|g')
SESSION_FILE="$HOME/.claude/projects/$ENC_CWD/$SESSION_ID.jsonl"
trap 'rm -f "$REPLY_FILE" "$SESSION_FILE"' EXIT

# PreToolUse: auto-approve every tool call so there's no interactive prompt.
PRE_CMD='echo "{\"hookSpecificOutput\":{\"hookEventName\":\"PreToolUse\",\"permissionDecision\":\"allow\"}}"'

# Stop: extract Claude's final reply from the hook payload and signal claude to exit.
STOP_CMD="jq -r .last_assistant_message > '$REPLY_FILE'; pid=\$PPID; while [ -n \"\$pid\" ] && [ \"\$pid\" != \"1\" ]; do name=\$(ps -p \$pid -o comm= 2>/dev/null); case \"\$name\" in *claude*) kill -INT \$pid; exit 0;; esac; pid=\$(ps -o ppid= -p \$pid 2>/dev/null | tr -d ' '); done"

SETTINGS=$(jq -nc --arg pre "$PRE_CMD" --arg stop "$STOP_CMD" '{
  hooks: {
    PreToolUse: [{hooks: [{type: "command", command: $pre}]}],
    Stop:       [{hooks: [{type: "command", command: $stop}]}]
  }
}')

script -q /dev/null claude --settings "$SETTINGS" --session-id "$SESSION_ID" "$PROMPT" >/dev/null 2>&1 || true

cat "$REPLY_FILE"