Project Session Manager

Project Session Manager (PSM) Skill

Native Subagent Protocol (Codex)

Codex supports native subagents. Delegate with spawn_agent, coordinate with send_input, collect via wait_agent, and clean up with close_agent.

Execution preference:

1. Use native subagents first for independent workstreams (parallel when possible).
2. Merge results in main thread and run final verification.
3. Fallback only when delegation is blocked: use the [ANALYST]/[ARCHITECT]/[EXECUTOR]/[REVIEWER] structure in a single response.

Minimal orchestration pattern:

spawn_agent -> send_input (optional) -> wait_agent -> close_agent

Codex invocation: use $project-session-manager ... or project-session-manager: ...

Automate isolated development environments using git worktrees and tmux sessions with Codex. Enables parallel work across multiple tasks, projects, and repositories.

Commands

Project References

Supported formats:

• Alias: omc#123 (requires ~/.psm/projects.json)
• Full: owner/repo#123
• URL: https://github.com/owner/repo/pull/123
• Current: #123 (uses current directory's repo)

Configuration

Project Aliases (~/.psm/projects.json)

{
  "aliases": {
    "omc": {
      "repo": "Yeachan-Heo/oh-my-codex",
      "local": "~/Workspace/oh-my-codex",
      "default_base": "main"
    }
  },
  "defaults": {
    "worktree_root": "~/.psm/worktrees",
    "cleanup_after_days": 14
  }
}

Directory Structure

~/.psm/
├── projects.json       # Project aliases
├── sessions.json       # Active session registry
└── worktrees/          # Worktree storage
    └── <project>/
        └── <type>-<id>/

Session Naming

Implementation Protocol

When the user invokes a PSM command, follow this protocol:

Parse Arguments

Parse {{ARGUMENTS}} to determine:

1. Subcommand: review, fix, feature, list, attach, kill, cleanup, status
2. Reference: project#number, URL, or session ID
3. Options: --branch, --base, --no-codex, --no-tmux, etc.

Subcommand: review <ref>

Purpose: Create PR review session

Steps:

1. Resolve reference:

   # Read project aliases
   cat ~/.psm/projects.json 2>/dev/null || echo '{"aliases":{}}'
   
   # Parse ref format: alias#num, owner/repo#num, or URL
   # Extract: project_alias, repo (owner/repo), pr_number, local_path
   

2. Fetch PR info:

   gh pr view <pr_number> --repo <repo> --json number,title,author,headRefName,baseRefName,body,files,url
   

3. Ensure local repo exists:

   # If local path doesn't exist, clone
   if [[ ! -d "$local_path" ]]; then
     git clone "https://github.com/$repo.git" "$local_path"
   fi
   

4. Create worktree:

   worktree_path="$HOME/.psm/worktrees/$project_alias/pr-$pr_number"
   
   # Fetch PR branch
   cd "$local_path"
   git fetch origin "pull/$pr_number/head:pr-$pr_number-review"
   
   # Create worktree
   git worktree add "$worktree_path" "pr-$pr_number-review"
   

5. Create session metadata:

   cat > "$worktree_path/.psm-session.json" << EOF
   {
     "id": "$project_alias:pr-$pr_number",
     "type": "review",
     "project": "$project_alias",
     "ref": "pr-$pr_number",
     "branch": "<head_branch>",
     "base": "<base_branch>",
     "created_at": "$(date -Iseconds)",
     "tmux_session": "psm:$project_alias:pr-$pr_number",
     "worktree_path": "$worktree_path",
     "source_repo": "$local_path",
     "github": {
       "pr_number": $pr_number,
       "pr_title": "<title>",
       "pr_author": "<author>",
       "pr_url": "<url>"
     },
     "state": "active"
   }
   EOF
   

6. Update sessions registry:

   # Add to ~/.psm/sessions.json
   

7. Create tmux session:

   tmux new-session -d -s "psm:$project_alias:pr-$pr_number" -c "$worktree_path"
   

8. Launch Codex (unless --no-codex):

   tmux send-keys -t "psm:$project_alias:pr-$pr_number" "codex" Enter
   

9. Output session info:

   Session ready!
   
     ID: omc:pr-123
     Worktree: ~/.psm/worktrees/omc/pr-123
     Tmux: psm:omc:pr-123
   
   To attach: tmux attach -t psm:omc:pr-123
   

Subcommand: fix <ref>

Purpose: Create issue fix session

Steps:

1. Resolve reference (same as review)

2. Fetch issue info:

   gh issue view <issue_number> --repo <repo> --json number,title,body,labels,url
   

3. Create feature branch:

   cd "$local_path"
   git fetch origin main
   branch_name="fix/$issue_number-$(echo "$title" | tr ' ' '-' | tr '[:upper:]' '[:lower:]' | head -c 30)"
   git checkout -b "$branch_name" origin/main
   

4. Create worktree:

   worktree_path="$HOME/.psm/worktrees/$project_alias/issue-$issue_number"
   git worktree add "$worktree_path" "$branch_name"
   

5. Create session metadata (similar to review, type="fix")

6. Update registry, create tmux, launch codex (same as review)

Subcommand: feature <project> <name>

Purpose: Start feature development

Steps:

1. Resolve project (from alias or path)

2. Create feature branch:

   cd "$local_path"
   git fetch origin main
   branch_name="feature/$feature_name"
   git checkout -b "$branch_name" origin/main
   

3. Create worktree:

   worktree_path="$HOME/.psm/worktrees/$project_alias/feat-$feature_name"
   git worktree add "$worktree_path" "$branch_name"
   

4. Create session, tmux, launch codex (same pattern)

Subcommand: list [project]

Purpose: List active sessions

Steps:

1. Read sessions registry:

   cat ~/.psm/sessions.json 2>/dev/null || echo '{"sessions":{}}'
   

2. Check tmux sessions:

   tmux list-sessions -F "#{session_name}" 2>/dev/null | grep "^psm:"
   

3. Check worktrees:

   ls -la ~/.psm/worktrees/*/ 2>/dev/null
   

4. Format output:

   Active PSM Sessions:
   
   ID                 | Type    | Status   | Worktree
   -------------------|---------|----------|---------------------------
   omc:pr-123        | review  | active   | ~/.psm/worktrees/omc/pr-123
   omc:issue-42      | fix     | detached | ~/.psm/worktrees/omc/issue-42
   

Subcommand: attach <session>

Purpose: Attach to existing session

Steps:

1. Parse session ID: project:type-number

2. Verify session exists:

   tmux has-session -t "psm:$session_id" 2>/dev/null
   

3. Attach:

   tmux attach -t "psm:$session_id"
   

Subcommand: kill <session>

Purpose: Kill session and cleanup

Steps:

1. Kill tmux session:

   tmux kill-session -t "psm:$session_id" 2>/dev/null
   

2. Remove worktree:

   worktree_path=$(jq -r ".sessions[\"$session_id\"].worktree" ~/.psm/sessions.json)
   source_repo=$(jq -r ".sessions[\"$session_id\"].source_repo" ~/.psm/sessions.json)
   
   cd "$source_repo"
   git worktree remove "$worktree_path" --force
   

3. Update registry:

   # Remove from sessions.json
   

Subcommand: cleanup

Purpose: Clean up merged PRs and closed issues

Steps:

1. Read all sessions

2. For each PR session, check if merged:

   gh pr view <pr_number> --repo <repo> --json merged,state
   

3. For each issue session, check if closed:

   gh issue view <issue_number> --repo <repo> --json closed,state
   

4. Clean up merged/closed sessions:

   • Kill tmux session
   • Remove worktree
   • Update registry

5. Report:

   Cleanup complete:
     Removed: omc:pr-123 (merged)
     Removed: omc:issue-42 (closed)
     Kept: omc:feat-auth (active)
   

Subcommand: status

Purpose: Show current session info

Steps:

1. Detect current session from tmux or cwd:

   tmux display-message -p "#{session_name}" 2>/dev/null
   # or check if cwd is inside a worktree
   

2. Read session metadata:

   cat .psm-session.json 2>/dev/null
   

3. Show status:

   Current Session: omc:pr-123
   Type: review
   PR: #123 - Add webhook support
   Branch: feature/webhooks
   Created: 2 hours ago
   

Error Handling

Requirements

• git with worktree support (v2.5+)
• gh CLI (authenticated)
• tmux
• jq for JSON parsing

Initialization

On first run, create default config:

mkdir -p ~/.psm/worktrees ~/.psm/logs

# Create default projects.json if not exists
if [[ ! -f ~/.psm/projects.json ]]; then
  cat > ~/.psm/projects.json << 'EOF'
{
  "aliases": {
    "omc": {
      "repo": "Yeachan-Heo/oh-my-codex",
      "local": "~/Workspace/oh-my-codex",
      "default_base": "main"
    }
  },
  "defaults": {
    "worktree_root": "~/.psm/worktrees",
    "cleanup_after_days": 14,
    "auto_cleanup_merged": true
  }
}
EOF
fi

# Create sessions.json if not exists
if [[ ! -f ~/.psm/sessions.json ]]; then
  echo '{"version":1,"sessions":{},"stats":{"total_created":0,"total_cleaned":0}}' > ~/.psm/sessions.json
fi