opencode-devbox/AGENTS.md

AGENTS.md

Project overview

Docker image packaging opencode into a production-ready dev container. Two image variants (base and omos) are published to Docker Hub via Gitea Actions CI. Not a library or application — this is infrastructure (Dockerfile, entrypoint scripts, docker-compose, documentation).

File roles

• Dockerfile — single multi-stage build for both variants. OMOS variant is controlled by INSTALL_OMOS=true build arg; mempalace is controlled by INSTALL_MEMPALACE (default true). All GitHub-sourced binaries are pinned with version ARGs.
• entrypoint.sh — runs as root: UID/GID adjustment, SSH permissions, volume ownership fixes (skipped via .devbox-owner sentinel when ownership is already correct). Then drops to developer via gosu.
• entrypoint-user.sh — runs as developer: git config, opencode.jsonc generation (delegated to generate-config.py), skillset auto-deploy from mounted skillset repo, OMOS setup.
• rootfs/usr/local/lib/opencode-devbox/generate-config.py — generates ~/.config/opencode/opencode.jsonc from env vars. Never overwrites an existing config (checks both .json and .jsonc). Auto-registers MCP servers for detected tools (mempalace via mempalace-mcp, gitea-mcp, context7 remote endpoint).
• scripts/smoke-test.sh — post-build image verification. Asserts binary presence, opencode startup, entrypoint correctness, config generation idempotency, and image size thresholds. Used by both CI workflows.
• scripts/generate-dockerhub-md.py — generates DOCKER_HUB.md from README.md using explicit section rules. --check fails if the committed file is out of sync (enforced by the validate workflow).
• DOCKER_HUB.md — auto-generated from README. Do not edit directly. Pushed to Docker Hub description via CI API call. Must stay under 25 kB. Short description field must be ≤100 bytes.
• README.md — authoritative source documentation. Sections are selected/dropped/replaced for DOCKER_HUB.md per SECTION_RULES in scripts/generate-dockerhub-md.py.
• .gitea/workflows/validate.yml — lightweight amd64 build + smoke test on push to main and PRs. Also runs the DOCKER_HUB.md sync check.
• .gitea/workflows/docker-publish.yml — CI pipeline on tag push: smoke-test each variant on amd64, then full multi-arch (amd64 + arm64) build-and-push, then update Docker Hub description.

Versioning scheme

Tags follow v{opencode_version}[letter] — e.g. v1.14.20 for the first build on a new opencode release, and v1.14.20b, v1.14.20c, … for subsequent rebuilds on the same opencode version.

• The number tracks the opencode npm version (see OPENCODE_VERSION ARG in Dockerfile).
• No letter suffix on the first build of a new opencode version — the bare v{opencode_version} tag is the canonical release.
• Letter suffix is the build ordinal, starting at b for the second build. The letter a is never used — think of the suffix as counting rebuilds: b = 2nd, c = 3rd, d = 4th, …. For opencode version 1.14.20: first build v1.14.20, second v1.14.20b, third v1.14.20c, and so on.
• A letter suffix is only used for container-level rebuilds — tooling changes, CVE fixes, doc-driven rebuilds, entrypoint bugfixes — that don't change the underlying opencode version.

CI produces four Docker Hub tags per release: vX.Y.Z[n], latest, vX.Y.Z[n]-omos, latest-omos.

When bumping the opencode version, also bump OPENCODE_VERSION in Dockerfile and update the comment in .env.example if it names a specific model/version for context.

Critical conventions

• entrypoint.sh volume ownership loop — when adding a new named volume mount point, add it to the for dir in ... loop in entrypoint.sh so root-owned volumes get chowned on startup. The loop writes a .devbox-owner sentinel after a successful chown so subsequent starts skip the recursive walk. Users should not touch these files.
• Two docs to keep in sync (automated) — README.md is the source of truth. DOCKER_HUB.md is auto-generated by scripts/generate-dockerhub-md.py. When adding a new top-level section to README, either add it to SECTION_RULES in that script or the --check run will fail CI. .env.example must still be hand-updated to match Dockerfile/entrypoint behavior.
• GitHub/Gitea-sourced binaries float by default — gosu, fzf, git-lfs, nvim, bat, eza, zoxide, uv, gitea-mcp, Go, oh-my-opencode-slim all default to latest. Each build-time install step reads the /releases/latest Location redirect (or the go.dev JSON feed for Go) and derives the concrete version. Use the same ARCH case-switch pattern for multi-arch support (amd64/arm64). Intentional pins: OPENCODE_VERSION (drives the image tag), NODE_VERSION=22 (major pin), DEBIAN_VERSION=trixie-slim (OS base). Adding a new upstream tool: follow the existing floated-version pattern, don't hardcode a specific tag.
• Resolved versions are logged by the smoke test — scripts/smoke-test.sh prints a "Resolved component versions" table as its first step. CI logs always capture what got baked into a given image even when ARGs default to latest.
• Shell scripts use set -euo pipefail — both entrypoints are strict. Errors in volume chown or SSH permission operations are intentionally suppressed with || true.
• MemPalace install path — installed via uv tool install into /opt/uv-tools/mempalace/. Both the mempalace CLI and the mempalace-mcp MCP server binary are shipped as entry points by the mempalace package itself and placed on PATH by uv as shims whose shebangs point at the venv's Python. No hand-rolled wrapper is needed. Do not use pip install --break-system-packages — that was the previous approach and has been removed. Do not use ["python3", "-m", "mempalace.mcp_server"] in opencode.jsonc — system Python can't import from the uv venv.
• generate-config.py idempotency — the script MUST never overwrite an existing opencode.jsonc or legacy opencode.json. Config persists in the devbox-opencode-config named volume; accidentally clobbering that file would destroy hand-edits. The smoke test asserts this.
• Skillset auto-deploy — on every container start, entrypoint-user.sh looks for a skillset repo (detection order: $SKILLSET_CONTAINER_PATH → $HOME/skillset → /workspace/skillset) and runs deploy-skills.sh --bootstrap --prune-stale. This creates relative symlinks in ~/.agents/skills/ and ~/.config/opencode/instructions/. Do NOT bind-mount ~/.agents/skills/ from the host — the container manages its own skills with relative symlinks that differ from the host's. The named volume devbox-opencode-config persists the deployed config across restarts.
• Config persistence via named volume — devbox-opencode-config is a Docker named volume mounted at ~/.config/opencode/. It is NOT a host bind mount by default. This separation allows both native and containerized opencode to coexist on the same machine without symlink conflicts. Users who need to override can replace the named volume with a host bind mount in their compose file.
• Docker Hub description update — uses /v2/auth/token endpoint (not the deprecated /v2/users/login). Auth uses identifier/secret fields, returns access_token, sent as Bearer. Short description must be ≤100 bytes.

CI quirks

• Both build jobs include an IPv4 preference step (gai.conf + driver-opts: network=host for buildx) to work around intermittent IPv6 failures on the Gitea runners.
• update-description job runs only when both builds succeed (needs: [build-base, build-omos]).
• Tags must be pushed to trigger the publish workflow. The validate workflow runs on push to main and PRs.
• Smoke tests run on amd64 only (single-arch load into the local daemon). The multi-arch push happens after smoke passes.
• Gitea Actions runner has ~40 GB disk, often 70%+ used at job start. All four load: true jobs (validate-base, validate-omos, smoke-base, smoke-omos) include a Reclaim runner disk step that strips catthehacker-resident toolchains and prunes stale docker state before setup-buildx-action. Build jobs use a lighter version (push-by-digest doesn't need docker system prune). Don't remove these steps without testing on a fresh runner.
• docker/build-push-action@v7 with platforms: linux/amd64,linux/arm64 handles multi-arch push natively in a single job — produces a proper manifest list, no matrix or merge step needed. An earlier revision split into per-arch matrix jobs with digest artifacts, but that pattern requires actions/{upload,download}-artifact@v4+ which Gitea Actions doesn't support (see below).
• actions/upload-artifact and actions/download-artifact must stay at @v3 on Gitea. v4+ uses a GitHub-Enterprise-specific Artifact API; runs fail with GHESNotSupportedError. If you need artifacts for a new reason (build logs, SBOMs, etc.), pin @v3 explicitly.
• Step scripts run under /bin/sh (dash), not bash. Avoid bash-isms like ${VAR//a/b} parameter-pattern substitution; use POSIX alternatives (tr, sed) or declare shell: bash on the step.
• BUILDKIT_PROGRESS=plain is set at workflow level on docker-publish.yml so arm64-under-QEMU builds log each layer line-by-line. The default collapsed progress UI hides which step is stalled, which made diagnosing earlier hangs expensive.

Testing changes

The smoke test (scripts/smoke-test.sh) is the canonical check and runs automatically in CI. To run locally:

# Base image
docker compose build
bash scripts/smoke-test.sh opencode-devbox --variant base

# OMOS image
docker build --build-arg INSTALL_OMOS=true -t opencode-devbox:omos .
bash scripts/smoke-test.sh opencode-devbox:omos --variant omos

For manual/exploratory testing:

1. docker compose run --rm devbox bash
2. Check specific tools inside: nvim --version, bat --version, uv --version, mempalace --help, etc.
3. For entrypoint changes: test with a non-1000 UID workspace to verify UID adjustment, volume ownership fixes, and the .devbox-owner sentinel behavior.
4. For generate-config.py changes: run standalone with HOME=/tmp/fake OPENCODE_PROVIDER=anthropic python3 rootfs/usr/local/lib/opencode-devbox/generate-config.py.

Commit style

Imperative mood, first line summarizes the change. Multi-line body explains "why" when non-obvious. Examples from history:

• Fix ownership of named volume mount points in entrypoint
• Add uv package manager to base image for on-demand Python support
• Upgrade base image from Debian bookworm to trixie (current stable)