# AGENTS.md

Guidance for coding agents working in this repository.

## Mission

Build `left4me` according to the two implementation plans:

- `docs/superpowers/plans/2026-04-22-l4d2-host-lib-v1.md`
- `docs/superpowers/plans/2026-04-23-l4d2-web-app-v1.md`

Do not invent architecture outside these plans unless explicitly requested.

## Current Project State

- `l4d2host/` and `l4d2web/` implementation directories exist.
- Implementation plans remain the source of truth for contract changes and task sequencing.

## Non-Negotiable Constraints

### Workspace and tools

- Do not use git worktrees.
- Repo is a uv workspace; Python is pinned to 3.13 via `.python-version`. After fresh checkout: install `uv` (`brew install uv` / `curl -LsSf https://astral.sh/uv/install.sh | sh`), then `direnv allow` (or `uv sync` directly). See README **Local development** for details.

### Dev server and filesystem paths

- **Production paths (`/var/lib/left4me`, `/usr/local/lib/systemd/system`, `/usr/local/libexec/left4me`, `/etc/left4me`) exist only on Linux deploy hosts.** Never create or write to these on a developer machine. They are referenced in `l4d2host/l4d2host/paths.py` and the spec only as the production layout.
- **For local dev, always use `scripts/dev-server.py`.** It sets `LEFT4ME_ROOT=./.tmp/dev-server`, runs migrations, seeds demo content (admin + blueprint + script overlay + files overlay), and starts Flask on port 5051. Reset state with `rm -rf .tmp/dev-server` then re-run. Never invoke `flask run` directly — that leaves `LEFT4ME_ROOT` unset and the app falls back to the production `/var/lib/left4me`, which on macOS surfaces as "route returns 404 / empty modal / file not found" and can be mistaken for a code bug.
- **All ephemeral dev state lives under `.tmp/`** (gitignored). Use `$TMPDIR` only for transient files outside the repo. Do NOT use `/tmp`, `~/Library/Application Support`, or any system path for project state — only `.tmp/` (project-local) or `$TMPDIR` (sandbox-blessed).
- **Symptom-to-cause translation:** if a route returns 404 or behaves as if the filesystem is empty, the first diagnosis is "`LEFT4ME_ROOT` is wrong" (defaulted to the production path), not "code bug." Restart via `scripts/dev-server.py`.

### Planning artifacts

- Design specs live in `docs/superpowers/specs/` as `YYYY-MM-DD-<topic>-design.md`.
- Implementation plans live in `docs/superpowers/plans/` as `YYYY-MM-DD-<topic>.md` (suffix the topic with `-v1`/`-v2`/etc. if a plan is versioned).
- Commit both to git as soon as the user approves them.
- Do not leave specs or plans outside this repo. The `~/.claude/plans/<slug>.md` plan-mode scratch file is acceptable while plan mode is open; the persisted artifact must end up under `docs/superpowers/` and be committed.

### Naming and boundaries

- Use `l4d2` naming consistently.
- Keep host library and web app as separate components.
- Do not collapse them into one package.

### Host library (`l4d2host` / `l4d2ctl`)

- Exposed CLI write command set is fixed:
  - `install`
  - `initialize <name> -f <spec.yaml>`
  - `start <name>`
  - `stop <name>`
  - `delete <name>`
- CLI read commands are allowed for web/host boundary consistency:
  - `status <name> --json`
  - `logs <name> --lines <n> --follow/--no-follow`
- Runtime paths are rooted at `LEFT4ME_ROOT`, defaulting to `/var/lib/left4me`.
- Deployment/config management owns global units under `/usr/local/lib/systemd/system` and privileged helpers under `/usr/local/libexec/left4me`.
- Overlay directories are populated by the web app (workshop downloads, managed-global refresh). The host library only mounts them.
- Fail-fast subprocess behavior; pass raw stderr; propagate return code.
- No lock manager, no rollback, no preflight runtime checks.
- Delete missing instance/runtime dirs must succeed (no-op).
- Read APIs required for web app integration:
  - `get_instance_status(name)`
  - `stream_instance_logs(name, lines=200, follow=True)`

### Web app (`l4d2-web-app`)

- Flask + server-rendered templates + vendored HTMX.
- No external frontend framework/dependencies.
- Custom CSS with tokenized, consistent link and accent colors.
- Local username/password auth and `admin` flag.
- Persist command logs in `job_logs` table (retain indefinitely).
- Desired vs actual server state model.
- Live logs in UI for both jobs and servers.
- Web app host operations go through `l4d2ctl` via a host command client, not direct `l4d2host` imports.
- Blueprint semantics (locked):
  - private per user in v1
  - live-linked to servers
  - no server-level overrides
  - deleting in-use blueprint is blocked
  - updates apply on next action
  - servers can reassign blueprint anytime

## Delivery Workflow

1. Read both plan files fully before coding.
2. Execute plan tasks in order.
3. Keep changes scoped to one task at a time.
4. Run task-level tests before moving forward.
5. Do not claim completion without command evidence.
6. Keep docs updated when behavior/contracts change.

## Verification Expectations

Before claiming success on any step, run the relevant command and report actual output status.

Typical commands (once components exist):

- `pytest l4d2host/tests -q`
- `pytest l4d2web/tests -q`

## Change Control

- If a requested change conflicts with this file, follow explicit user instruction.
- If plans and code diverge, update plans or flag the mismatch clearly.

## End-to-end tests

The Playwright-based browser tests under `l4d2web/tests/e2e/` need a
chromium binary, fetched on first setup:

```bash
uv run playwright install chromium
```

Always invoke as `uv run pytest -m e2e ...` (excluded from the default
fast suite via the `e2e` marker). Other forms crash Chromium under the
macOS sandbox; only this exact invocation is exempt.

## Editor bundle (CodeMirror 6)

The in-browser code editor on the blueprint config / overlay script /
files-modal textareas is bundled from `l4d2web/scripts/editor-src/`
via esbuild and committed pre-built to
`l4d2web/l4d2web/static/vendor/editor.bundle.js`. Source lives under
`l4d2web/scripts/editor-src/`; design and plan at
`docs/superpowers/specs/2026-05-17-textarea-editor-v2-design.md` and
`docs/superpowers/plans/2026-05-17-textarea-editor-v2.md`.

Rebuild after editing the source:

```bash
./l4d2web/scripts/build-editor.sh
```

Requires `node` + `npm` locally. The script overrides the npm cache to
`$TMPDIR/npm-cache` (set `NPM_CACHE` to override) to dodge root-owned
files in `~/.npm/_cacache/` from older npm versions. Commit the
regenerated `editor.bundle.js`, `editor.bundle.css`, and
`editor.bundle.sha256` alongside any source change.

Regenerate the autocomplete vocab from `./cvar_list` (live L4D2
cvarlist dump committed at repo root) after replacing the dump:

```bash
./l4d2web/scripts/build-vocab.py
```