# AGENTS.md

## What this is

Harness-side bring-up for the [pi coding-agent](https://github.com/earendil-works/pi).
Installs three pi-generic config artifacts into the right places and
runs a couple of non-halting probes. Does not depend on MemPalace.

Sibling to [`opencode-toolkit`](https://gitea.jordbo.se/joakimp/opencode-toolkit) —
same shape: one `install.sh` at the root, cp-or-symlink the config files,
probe the environment, compose independently of the palace memory layer.

Read [`README.md`](README.md) first for the user-facing walk-through.
This file is for agents modifying the repo.

## Structure

```
install.sh              # Idempotent installer (symlink + cp + probes)
pi-env.zsh              # Shell loader sourcing ~/.config/pi/.env (POSIX-compatible)
keybindings.json        # ~/.pi/agent/keybindings.json — mosh/tmux newline fix
settings.example.json   # Template for ~/.pi/agent/settings.json (copy + edit)
README.md               # User-facing quickstart + new-machine deploy recipe.
AGENTS.md               # This file.
LICENSE                 # MIT.
```

## Conventions

- **One install step per artifact**, with a matching uninstall step.
- **Symlink what's safe to symlink, cp what's part of a dotfiles backup,
  template what the harness rewrites.**
  - `keybindings.json` → symlink. pi doesn't rewrite it; the symlink
    lets edits flow through git without a re-install step.
  - `pi-env.zsh` → `cp` into `~/.oh-my-zsh/custom/`. That dir is
    typically part of a dotfiles backup (e.g. `myconfigs`'s
    `rsync_copy.sh`); a symlink into this repo's absolute path breaks
    when the backup is restored on another host.
  - `settings.example.json` → **not installed**. pi rewrites
    `~/.pi/agent/settings.json` at runtime (`lastChangelogVersion` bumps
    on upgrade), so any symlink back to the repo would dirty the
    working tree. Installer prints the `cp` command and walks away.
- **Probes warn, never halt.** `warn` + `return 0`. The installer's only
  hard-fail path is "pi isn't installed at all" — that's an early
  `exit 4` from `require_pi_installed` because there's nothing useful
  to do without `~/.pi/agent/`.
- **Non-destructive.** Existing real files at symlink destinations get
  backed up with a timestamp (`.bak.YYYYMMDD-HHMMSS`) before linking.
  The shell loader's cp path refuses to clobber local edits: detects
  drift via `cmp -s`, prints a `diff` hint, leaves the file alone.
- **Do not auto-edit rc files.** If oh-my-zsh isn't present, print the
  `source` snippet the user manually adds to `~/.zshrc` or `~/.bashrc`.
  Invasive shell-rc edits belong in a dotfiles installer, not here.
- **No hard dependency on mempalace.** If the surface ever grows
  mempalace-aware (unlikely — those pieces live in `mempalace-toolkit`
  on purpose), it must degrade gracefully when mempalace is absent.
- **POSIX-compatible shell glue.** `set -a` / `source` / `set +a` work
  in bash and zsh both. Don't add zsh-only constructs to files that
  may end up sourced from `~/.bashrc`.

## What `install.sh` does

Hard-required:
- `require_pi_installed` — aborts with exit 4 if `~/.pi/agent/` is missing.
  Creates `~/.pi/agent/extensions/` proactively so a later
  `mempalace-toolkit` install has somewhere to symlink into.

Always (once pi is present):
- Symlinks `keybindings.json` into `~/.pi/agent/`. Backs up any
  pre-existing real file.

oh-my-zsh path (gated on `~/.oh-my-zsh/custom/` existing):
- Copies `pi-env.zsh` into that directory. Drift-safe — prints a `diff`
  hint if installed content differs from repo, doesn't clobber.

No oh-my-zsh path:
- Prints a shell-specific source snippet for `~/.zshrc` or `~/.bashrc`
  (selected from `$SHELL`). User pastes manually.

Probes (non-halting):
- `~/.pi/agent/settings.json` exists. Without it pi refuses to start
  without `--provider`/`--model`. Prints the `cp settings.example.json`
  command.
- `AWS_PROFILE` + `AWS_REGION` are set, **only if** `settings.json`
  selects `amazon-bedrock`. Silent for non-Bedrock providers. Silent if
  settings.json is missing (check_pi_settings already handled that case).

## Adding a new artifact

Follow the same shape `keybindings.json` / `pi-env.zsh` / `settings.example.json` use:

1. **One file at repo root.** Flat layout; no `extensions/` subdir yet.
   Revisit if five+ artifacts ever accumulate.
2. **Choose symlink / cp / template** per the conventions above. Document
   the choice in a comment next to the variable declarations at the top
   of `install.sh`.
3. **One install step + one uninstall step** in `install.sh`, guarded by
   `link_if_into_repo` (for symlinks) or `cmp -s` (for copies). Never
   remove user edits silently.
4. **One probe per external dependency** the artifact implies. `warn` +
   `return 0`.
5. **Update this file's Structure block** and `README.md`.

## Adding mempalace-aware functionality

Don't. Those pieces belong in `mempalace-toolkit/extensions/pi/`:
- The mempalace MCP bridge TypeScript extension (`mempalace.ts`) —
  imports pi's `ExtensionAPI`, registers MCP tools, injects wake-up
  context.
- The `install_pi_extension` function that symlinks it in.
- Any probes that check for mempalace being reachable *through* pi.

That boundary is load-bearing for `opencode-devbox`'s slim container
path: a container built with `INSTALL_MEMPALACE=false` should install
pi-toolkit cleanly and get a functional pi without dragging in
chromadb + embedding models (~300 MB).

## Testing

No framework. Manual:

```bash
./install.sh --help                       # flags
./install.sh --yes                        # fresh install
./install.sh --yes                        # re-run (idempotent)
./install.sh --uninstall --yes            # remove
./install.sh --yes                        # reinstall
```

oh-my-zsh fallback simulation:

```bash
SHELL=/bin/bash HOME=/tmp/fake ./install.sh --yes   # should print ~/.bashrc snippet
```

Environment verification (after install + `exec zsh` or new shell):

```bash
zsh -ic 'echo $AWS_PROFILE $AWS_REGION'   # should print values from ~/.config/pi/.env
```

Drift simulation:

```bash
echo "# local edit" >> ~/.oh-my-zsh/custom/pi-env.zsh
./install.sh --yes                        # should warn "differs from repo" and leave alone
```

## Gotchas

- **pi must be installed upstream first.** `~/.pi/agent/` is created by
  pi on first run, not by this installer. Missing → exit 4 with
  pointer to https://github.com/earendil-works/pi.
- **`settings.example.json` is region-specific.** The shipped default
  uses `eu.` Bedrock inference-profile prefixes. Users on us-east need
  to swap to `us.` before first run, or pi will reject the model ID.
- **Bedrock is not the only provider.** If the user is on bare
  Anthropic or OpenAI, `AWS_PROFILE` / `AWS_REGION` are irrelevant. The
  probe gates on `grep -q '"amazon-bedrock"' settings.json` to stay
  quiet in those cases.
- **Mosh strips modifiers upstream of tmux.** The keybindings file's
  `ctrl+j` / `alt+j` fallbacks are specifically because mosh's vt220-ish
  emulation does not forward `Shift+Enter` as CSI-u — tmux's
  `extended-keys csi-u` setting doesn't help over mosh (only helps on
  direct ssh / local / WireGuard). Documented in README.
- **The shell loader runs on every shell start.** Keep it fast. If it
  grows beyond a few lines, gate on `[[ $- == *i* ]]` so
  non-interactive shells skip the work.
- **`~/.config/pi/.env` should be chmod 600.** It's plaintext on disk;
  git-crypt encryption only applies in the dotfiles repo. The installer
  does not enforce this because it doesn't ship the file.

## Related repos

- [`mempalace-toolkit`](https://gitea.jordbo.se/joakimp/mempalace-toolkit)
  — adds a pi↔mempalace MCP bridge on top of this toolkit. Installs the
  `mempalace.ts` extension into `~/.pi/agent/extensions/`. Optional.
- [`opencode-toolkit`](https://gitea.jordbo.se/joakimp/opencode-toolkit)
  — sibling pattern for the opencode coding-agent. Same install.sh
  shape.
- [`opencode-devbox`](https://gitea.jordbo.se/joakimp/opencode-devbox)
  — Docker containers; composes any subset of these toolkits via
  independent install.sh invocations.
- [`myconfigs`](https://gitea.jordbo.se/joakimp/myconfigs) — dotfiles
  repo where `~/.config/pi/.env` is tracked (git-crypt encrypted).

## History

Split out of `mempalace-toolkit/extensions/pi/` on 2026-05-05. Previously
the pi-generic config artifacts (env loader, keybindings, settings
template) lived alongside the `mempalace.ts` MCP bridge inside
mempalace-toolkit because that's where the pattern first crystallized.
The split was motivated by `opencode-devbox`'s mempalace opt-out and
future pi-option: a container built with mempalace off should still be
able to install a functional pi, and that dependency asymmetry is
cleanest when pi's own config lives in its own repo. Mirrors the
2026-05-05 split of `opencode-toolkit` out of the same parent.