# AGENTS.md

## Project overview

This repository builds and publishes a Docker image for [OpenCode](https://opencode.ai), the open source AI coding agent. The image ships OpenCode 2, runs it in headless server mode (`opencode serve`), and is automatically rebuilt and pushed to Docker Hub (`jcabillot/opencode`) every night by a Gitea Actions pipeline.

## Repository structure

```
.
├── Dockerfile                            # Image definition
├── .gitea/workflows/docker-build.yaml    # CI/CD pipeline (Gitea Actions)
├── renovate.json                         # Dependency update automation (Renovatebot)
├── opencode-attach                       # Helper script for attaching to a running server
└── README.md                             # Usage documentation
```

## Dependency management

- **Always pin versions** in the Dockerfile `npm install` command (e.g. `@opencode/cli@2.0.32 n2-soul@9.0.9`). Never leave packages unpinned.
- **Update renovate customManagers** when adding, removing, or renaming a dependency tracked in the Dockerfile. Each pinned package must have a corresponding `customManager` entry in `renovate.json` with a regex `matchStrings` pattern that captures the version. If a dependency is added without a renovate entry, Renovatebot will not open automated PRs for it.
- **apt packages** (apt-get install lines in Dockerfile) and **COPY --from** image references are not currently tracked by Renovate. Pinning these manually is acceptable for now but adding renovate managers for them is encouraged.

## Dockerfile conventions

- **Base image**: `node:26-trixie` — Debian-based Node.js image (not Alpine) so that downstream images can still use `apt-get` and Node-based MCP servers keep working.
- **Install**: `npm i -g @opencode/cli@<version> n2-soul@<version>` — installs OpenCode 2 and Soul globally, both pinned. `@opencode/cli` replaced `opencode-ai` as the published package in OpenCode 2; `--allow-scripts=@opencode/cli` is required for its `postinstall` to select the native binary.
- **Version check**: `RUN opencode --version` after install to validate the build and record the installed version in build logs.
- **Dedicated user**: a non-root `opencode` user and group are created with `groupadd`/`useradd` (UID/GID 1000). All runtime steps run as this user.
- **Cluster tooling**: `kubectl` is copied from the official `registry.k8s.io/kubectl` image (multi-stage COPY).
- **Entrypoint**: `["opencode"]` — arguments are passed at runtime; `serve` starts the headless server. Bare `opencode` opens the TUI, so the server is always invoked explicitly.

## OpenCode 2 notes

- The npm package is `@opencode/cli` (bins `opencode` and `opencode2`); `opencode-ai` stops at 1.19.x and must not come back.
- `opencode attach` no longer exists: point a client at a server with `opencode --server <url>` (after the subcommand when one is given). `opencode-attach` wraps this.
- The server always authenticates: username is fixed to `opencode`, password comes from `OPENCODE_SERVER_PASSWORD` or `OPENCODE_PASSWORD`, and a random one is generated and logged when neither is set.
- The v1 REST API was replaced (`/global/health` is gone, every route now lives under `/api/*` and requires auth). Any client calling the v1 API — e.g. `perso/opencode-dispatch` — must be migrated separately.

## CI/CD conventions (Gitea Actions)

- Pipeline triggers on push to `main`, PRs targeting `main`, and a nightly cron (`cron: '0 0 * * *'`).
- Image is pushed to Docker Hub only on non-PR events (main branch pushes and cron runs).
- Docker Hub credentials are stored in Gitea Actions secrets (`DOCKERHUB_USERNAME`, `DOCKERHUB_TOKEN`).
- The image is published as `jcabillot/opencode:latest` with digest and branch tags.

## Useful commands

```bash
# Build the image locally
docker build -t opencode .

# Run the server on all interfaces
docker run -it -p 4096:4096 opencode serve --hostname 0.0.0.0

# Run with a project mounted
docker run -it -p 4096:4096 \
  -v $(pwd):/home/opencode/project \
  opencode serve --hostname 0.0.0.0

# Protect with a password
docker run -it -p 4096:4096 \
  -e OPENCODE_SERVER_PASSWORD=secret \
  opencode serve --hostname 0.0.0.0
```

## opencode serve options

| Flag | Default | Description |
|------|---------|-------------|
| `--port` | `4096` | Port to listen on |
| `--hostname` | `127.0.0.1` | Hostname to bind |
| `--cors` | `[]` | Additional allowed browser origins (repeatable) |
| `--service` | `false` | Run as the shared background service |
| `--stdio` | `false` | Serve over stdio for editor integrations |

## Environment variables

| Variable | Description |
|----------|-------------|
| `OPENCODE_SERVER_PASSWORD` | Server password (HTTP basic auth, username `opencode`) |
| `OPENCODE_PASSWORD` | Same, takes precedence over `OPENCODE_SERVER_PASSWORD` |

`OPENCODE_SERVER_USERNAME` existed in OpenCode 1 and is no longer read: the username is always `opencode`.