Hooks

Where it lives

• hooks/mnemos-session-start.shGitHub ↗
  Read the script

  #!/bin/bash
  # Mnemos SessionStart hook — inject last checkpoint on resume/clear/compact.
  # Also sets usage summary baseline for per-session decision counting.
  # No set -euo pipefail: hook scripts must be defensive, not strict.
  
  # Set usage summary baseline (decisions before this session started)
  LOG="$HOME/.claude/routing-log.jsonl"
  TODAY=$(date -u +%Y-%m-%d)
  if [ -f "$LOG" ]; then
    grep -c "$TODAY" "$LOG" 2>/dev/null > "$HOME/.claude/usage-session-baseline" || true
  fi
  
  INPUT=$(cat 2>/dev/null || true)
  CWD=$(echo "$INPUT" | jq -r '.cwd // empty' 2>/dev/null || true)
  SESSION_TYPE=$(echo "$INPUT" | jq -r '.type // empty' 2>/dev/null || true)
  
  # Fallback: if jq failed (non-JSON input), extract from raw text
  if [ -z "$CWD" ]; then
    CWD="."
  fi
  if [ -z "$SESSION_TYPE" ]; then
    case "${INPUT:-}" in
      *clear*)  SESSION_TYPE="clear" ;;
      *compact*) SESSION_TYPE="compact" ;;
      *resume*) SESSION_TYPE="resume" ;;
      *startup*) SESSION_TYPE="startup" ;;
      *) SESSION_TYPE="unknown" ;;
    esac
  fi
  
  if [ ! -d "$CWD/.mnemos" ]; then
    exit 0
  fi
  
  # Get checkpoint from mnemos
  RESULT=$(echo "{\"cwd\":\"$CWD\"}" | \
    python3 -m mnemos _hook session_start 2>/dev/null || echo "")
  
  if [ -z "$RESULT" ]; then
    exit 0
  fi
  
  # For clear/compact: append auto-announce instruction via Python
  # For resume/startup: pass through unchanged
  if [ "$SESSION_TYPE" = "clear" ] || [ "$SESSION_TYPE" = "compact" ]; then
    python3 -c "
  import json, sys
  
  session_type = sys.argv[1]
  raw = sys.argv[2]
  
  try:
      data = json.loads(raw)
  except Exception:
      sys.exit(0)
  
  ctx = data.get('hookSpecificOutput', {}).get('additionalContext', '')
  if not ctx:
      sys.exit(0)
  
  announce = (
      '\n\nAUTO-ANNOUNCE: Context was just restored after /'
      + session_type
      + '. You MUST proactively tell the user what they were working on '
      'based on the checkpoint above. Start your response with a brief '
      'summary: goal, what was completed, current constraints, and '
      'immediate next steps. Do NOT wait for the user to ask.'
  )
  data['hookSpecificOutput']['additionalContext'] = ctx + announce
  json.dump(data, sys.stdout)
  " "$SESSION_TYPE" "$RESULT" 2>/dev/null || echo "$RESULT"
  else
    echo "$RESULT"
  fi
  
  exit 0
  

Read the script before you install anything that runs on your machine. This is the one part of a plugin that acts without being asked.