Hooks

Where it lives

• hooks/session-start.shRunsGitHub ↗
  Read the script

  #!/usr/bin/env bash
  # Injects the mentor stance (+ the user's profile, if set up) into every session
  # as SessionStart additionalContext. Runs under Claude Code and Codex — both fire
  # SessionStart hooks with the same schema, and Codex sets CLAUDE_PLUGIN_ROOT for
  # compatibility. Never fails the session: any error exits 0 with no output, which
  # the harness treats as "no extra context".
  
  set -uo pipefail
  
  # Where the profile and todos live. An explicit $MENTOR_HOME wins; otherwise
  # reuse whichever directory already holds a profile, so an existing setup keeps
  # working when the plugin is installed in the other agent too.
  MENTOR_DIR="${MENTOR_HOME:-}"
  if [ -z "$MENTOR_DIR" ]; then
    for candidate in "$HOME/.mentor" "$HOME/.claude/mentor" "${CODEX_HOME:-$HOME/.codex}/mentor"; do
      if [ -r "$candidate/profile.md" ]; then
        MENTOR_DIR="$candidate"
        break
      fi
    done
  fi
  [ -n "$MENTOR_DIR" ] || MENTOR_DIR="$HOME/.mentor"
  
  PROFILE="$MENTOR_DIR/profile.md"
  STANCE="${CLAUDE_PLUGIN_ROOT:-$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)}/stance.md"
  
  [ -r "$STANCE" ] || exit 0
  
  body="$(cat "$STANCE")"
  body+=$'\n\n---\n\n# Mentor directory\n\nThis user\'s mentor directory is `'"$MENTOR_DIR"$'`. Its two files are the profile\nat `'"$PROFILE"$'` and the todo file at `'"$MENTOR_DIR"$'/todos.md`. Either may be a\nsymlink pointing elsewhere; follow it without comment. Use these paths, not any\ndefault mentioned elsewhere.'
  
  if [ -r "$PROFILE" ]; then
    body+=$'\n\n---\n\n# This user\'s profile\n\nThe user wrote this themselves during mentor setup. It is the yardstick for the\nstance above — if they ask to change a goal, edit a shortcoming, or add to the\ndon\'t-let-me list, edit the profile file directly.\n\n'
    body+="$(cat "$PROFILE")"
  else
    body+=$'\n\n---\n\n# No profile yet\n\nThis user has not set up a mentor profile, so the stance above has no yardstick\nand cannot function. At the next natural pause — not mid-task — mention once\nthat setting one up takes a few minutes: `/mentor:init` in Claude Code, or in\nCodex just ask to set up the mentor profile. Say it once per session at most.\nDo not nag, and do not invent goals for them in the meantime.'
  fi
  
  # JSON-encode safely: the profile contains quotes, newlines and likely non-ASCII.
  if command -v python3 >/dev/null 2>&1; then
    printf '%s' "$body" | python3 -c 'import json,sys; print(json.dumps({"hookSpecificOutput":{"hookEventName":"SessionStart","additionalContext":sys.stdin.read()}}))'
  else
    # Fallback: minimal escaper, good enough for the stance text alone.
    esc=$(printf '%s' "$body" | sed -e 's/\\/\\\\/g' -e 's/"/\\"/g' | awk '{printf "%s\\n", $0}')
    printf '{"hookSpecificOutput":{"hookEventName":"SessionStart","additionalContext":"%s"}}\n' "$esc"
  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.