# HQ Terminal — Implementation Plan

Reference spec: `.hq/2026-06-09-spec-hq-terminal.md`

## Phase 1: Project Scaffold

Set up the new workspace with tooling, dependencies, and basic structure.

### Steps

1. **Create workspace** at `~/dev/hqt/` with `uv init --lib --name hqt`
2. **Configure pyproject.toml**:
   - Python ≥ 3.12
   - Dependencies: `textual>=2.0`, `sqlalchemy>=2.0`, `click>=8.0`
   - Dev dependencies: `pytest`, `pytest-asyncio`, `ruff`
   - Entry point: `[project.scripts] hqt = "hqt.cli:main"`
3. **Create package structure** per spec: `src/hqt/` with all subdirectories
4. **Create `.hq/PROJECT.md`** for the new project
5. **Verify**: `uv run hqt --help` produces output

## Phase 2: Database Layer

SQLite models, engine, and schema management.

### Steps

1. **`src/hqt/config.py`** — Settings dataclass with paths:
   - `db_path`: `~/.local/share/hqt/hqt.db`
   - `config_dir`: `~/.config/hqt/`
   - `skills_dir`: `~/.config/hqt/skills/`
   - `tmux_path`: `tmux`
   - `tui_session_name`: `hqt-main`
2. **`src/hqt/db/models.py`** — SQLAlchemy models: `Project`, `Harness`, `Session`, `McpServer`, `ProjectMcpServer`, `ProjectSkill`
3. **`src/hqt/db/session.py`** — Engine factory, session factory, `ensure_db()` (creates dir + tables)
4. **`src/hqt/db/migrate.py`** — Additive migration helper (add missing columns)
5. **Tests**: model creation, ensure_db on fresh + existing databases
6. **Verify**: `uv run pytest tests/test_db.py -q` passes

## Phase 3: TmuxRunner

The async tmux command abstraction. Largely ported from HQ.

### Steps

1. **`src/hqt/tmux/runner.py`** — Port `TmuxRunner` from HQ:
   - `new_session(name, cwd, command, width, height)`
   - `has_session(name) -> bool`
   - `kill_session(name)`
   - `send_text(name, text)`
   - `send_enter(name)`
   - `capture_pane(name) -> str`
   - `switch_client(target)` ← NEW (not in HQ)
   - `list_sessions() -> list[str]` ← NEW
2. **`src/hqt/tmux/manager.py`** — Higher-level session lifecycle:
   - `spawn_session(session: Session, config: SpawnConfig) -> None`
   - `resume_session(session: Session, config: SpawnConfig) -> None`
   - `kill_session(session: Session) -> None`
   - `attach_session(session: Session) -> None` (switch-client)
   - `is_alive(session: Session) -> bool`
   - `poll_all_sessions(sessions: list[Session]) -> dict[int, bool]`
3. **Tests**: mock `_exec` function, verify command construction
4. **Verify**: `uv run pytest tests/test_tmux.py -q` passes

## Phase 4: Harness Abstraction Layer

The configurator protocol and concrete implementations.

### Steps

1. **`src/hqt/harnesses/base.py`** — `HarnessConfigurator` protocol, `SpawnConfig`, `HarnessIdentity` dataclasses
2. **`src/hqt/harnesses/claude.py`** — Claude Code configurator:
   - UUID generation via `uuid5`
   - Spawn: `claude --session-id {uuid} --model {model}`
   - Resume: `claude --resume {uuid}`
   - MCP: write project `.mcp.json`
   - Skills: write/append `CLAUDE.md`
   - Ready/busy regexes from terminal profiles
3. **`src/hqt/harnesses/kiro.py`** — Kiro CLI configurator (stub for now):
   - Basic spawn command
   - MCP: Kiro-managed (no injection in v1)
4. **`src/hqt/harnesses/aider.py`** — Aider configurator:
   - Spawn: `aider --model {model} --restore-chat-history`
   - Skills: `--read {skill_file}` flags
   - No MCP support
5. **`src/hqt/harnesses/generic.py`** — Fallback for unknown harnesses:
   - Env-var based config only
6. **`src/hqt/harnesses/registry.py`** — Discover available harnesses (`shutil.which`), return configurator instances
7. **Tests**: each configurator produces correct SpawnConfig for given inputs
8. **Verify**: `uv run pytest tests/test_harnesses.py -q` passes

## Phase 5: Skills & MCP Services

Skill registry and MCP server management.

### Steps

1. **`src/hqt/skills/registry.py`** — Port from HQ: scan `skills_dir`, parse frontmatter, return `Skill` objects
2. **`src/hqt/skills/injection.py`** — Port from HQ: `wrap_prompt_with_skills()`
3. **`src/hqt/mcp/service.py`** — CRUD for MCP servers and project bindings (DB operations)
4. **`src/hqt/projects/service.py`** — Project CRUD: add, list, archive, git status reading
5. **Tests**: skill discovery with fixture directory, MCP CRUD, project CRUD
6. **Verify**: `uv run pytest tests/test_skills.py tests/test_mcp.py tests/test_projects.py -q` passes

## Phase 6: Session Service (Orchestration Core)

The service that ties together DB, tmux, and harness configurators.

### Steps

1. **`src/hqt/sessions/service.py`** — Session lifecycle:
   - `create_session(project_id, harness_name, nickname, model, skill_names, mcp_ids) -> Session`
     - Generates harness UUID via configurator
     - Builds SpawnConfig
     - Calls tmux manager to spawn
     - Persists session row
   - `resume_session(session_id) -> None`
     - Loads session from DB
     - Builds resume SpawnConfig with stored UUID
     - Calls tmux manager to spawn
   - `stop_session(session_id) -> None`
     - Kills tmux session
     - Updates DB (last_activity_at)
   - `delete_session(session_id) -> None`
     - Kills tmux if alive
     - Removes DB row
   - `attach_session(session_id) -> None`
     - Calls tmux switch-client
   - `list_sessions(project_id) -> list[SessionInfo]`
     - Joins DB data with tmux liveness
2. **Tests**: mock tmux manager, verify session lifecycle
3. **Verify**: `uv run pytest tests/test_sessions.py -q` passes

## Phase 7: Textual TUI

The user interface.

### Steps

1. **`src/hqt/tui/app.py`** — Textual `App` subclass:
   - Bindings: q=quit, n=new session, a=add project, /=filter
   - Compose: Header, ProjectList, SessionList, Footer
   - Timer: poll tmux liveness every 3s
2. **`src/hqt/tui/widgets/project_list.py`** — ListView of projects:
   - Shows name, path, branch
   - Selection updates session list
   - Keybindings: Enter=select, a=add, d=archive
3. **`src/hqt/tui/widgets/session_list.py`** — ListView of sessions for selected project:
   - Shows harness icon, nickname, alive/dead status
   - Keybindings: Enter=attach, n=new, d=delete, r=rename, R=resume (if dead)
4. **`src/hqt/tui/screens/new_session.py`** — Modal screen:
   - Harness selector (dropdown)
   - Nickname input
   - Model selector (populated from configurator.supported_models)
   - Skills multi-select
   - MCP servers multi-select
   - Create / Cancel buttons
5. **`src/hqt/tui/screens/add_project.py`** — Modal:
   - Path input (with directory completion if feasible, or paste)
   - Name override (optional)
6. **`src/hqt/tui/styles.tcss`** — Textual CSS for layout
7. **Integration test**: App mounts, projects display, key bindings respond
8. **Verify**: `uv run pytest tests/test_tui.py -q` passes (headless Textual testing)

## Phase 8: CLI Entry Point & tmux Bootstrap

Wire everything together.

### Steps

1. **`src/hqt/cli.py`** — Click CLI:
   - `hqt` (default) — bootstrap into tmux + launch TUI
   - `hqt list` — print projects/sessions table
   - `hqt attach <id>` — switch to session
   - `hqt new <project> <harness>` — create session non-interactively
   - `hqt doctor` — check tmux, harness availability
2. **`src/hqt/__main__.py`** — `python -m hqt` support
3. **tmux bootstrap logic**:
   ```python
   def bootstrap():
       if not in_tmux():
           # Create hqt-main session with TUI as the command
           exec tmux new-session -s hqt-main "hqt --inside-tmux"
       else:
           # Already in tmux, just run the TUI
           run_tui()
   ```
4. **First-run setup**: suggest tmux keybinding, create config dir/skills dir
5. **Verify**: `hqt doctor` works, `hqt` launches TUI inside tmux

## Phase 9: Integration Testing & Polish

### Steps

1. **End-to-end test**: create project → create session → verify tmux session exists → attach → kill → verify dead
2. **Handle edge cases**:
   - tmux not installed → clear error
   - Harness not found → show in UI, disable create
   - DB locked → retry pattern
   - Session name collision → fail gracefully
3. **README.md** with quick start
4. **Verify**: full test suite passes, manual smoke test with claude-code

## Dependency Graph

```
Phase 1 (scaffold)
    │
    ├── Phase 2 (database)
    │       │
    │       ├── Phase 5 (skills + MCP)
    │       │       │
    │       │       └──────┐
    │       │              │
    │       └── Phase 6 (session service) ◄── Phase 4 (harness abstraction)
    │               │
    ├── Phase 3 (tmux runner) ──────────────┘
    │                                        │
    │                                        ▼
    └── Phase 7 (TUI) ◄──────────── Phase 6
            │
            ▼
        Phase 8 (CLI + bootstrap)
            │
            ▼
        Phase 9 (integration + polish)
```

## Estimated Effort

| Phase | Complexity | Approx. LOC |
|-------|-----------|-------------|
| 1. Scaffold | Low | ~50 (config) |
| 2. Database | Low | ~150 |
| 3. TmuxRunner | Low | ~120 (mostly port) |
| 4. Harness abstraction | Medium | ~300 |
| 5. Skills + MCP | Low | ~150 (mostly port) |
| 6. Session service | Medium | ~200 |
| 7. TUI | Medium-High | ~400 |
| 8. CLI + bootstrap | Low | ~100 |
| 9. Integration | Medium | ~150 |
| **Total** | | **~1,620** |

## Implementation Order (sequential for a single agent)

1. Phase 1 → 2. Phase 2 → 3. Phase 3 → 4. Phase 4 → 5. Phase 5 → 6. Phase 6 → 7. Phase 7 → 8. Phase 8 → 9. Phase 9

Each phase produces a working, testable increment. The TUI (Phase 7) is the largest single piece but depends on everything below it being solid.