docs: fix quick-start — bare 'run devbox' lands in a shell, not opencode

The image's default CMD is bash -l, so 'docker compose run --rm devbox'
with no command drops into a login shell; you pass 'opencode' explicitly to
start the harness. The README quick-start claimed the opposite and carried a
garbled 'Use bash instead of (no command)' half-sentence; the same error was
mirrored in the Hub HUB_TEMPLATE. Fix both and regenerate DOCKER_HUB.md.
Doc-only — no image bytes change.

CHANGELOG.md

@@ -8,6 +8,15 @@ Tags follow `v{opencode_version}[letter]` — bare tag for the first build on a
 
 ## Unreleased
 
+### Docs (no image change)
+
+- Fix the quick-start description in `README.md` and the Hub `HUB_TEMPLATE`
+  (`scripts/generate-dockerhub-md.py`, regenerated `DOCKER_HUB.md`): bare
+  `docker compose run --rm devbox` lands in a **login shell** (default `CMD` is
+  `bash -l`), not opencode. The old copy claimed the opposite and had a garbled
+  "Use `bash` instead of (no command)" half-sentence. Pass `opencode` explicitly
+  to start the harness directly. Doc-only — does not trigger a new image build.
+
 ## v2.1.0 — 2026-06-13
 
 Image-semver **minor**: adds the OMOS bundled-skills image-symlink mechanism and

DOCKER_HUB.md

@@ -34,7 +34,7 @@ curl -fsSL https://gitea.jordbo.se/joakimp/opencode-devbox/raw/branch/main/.env.
 docker compose run --rm devbox
 ```
 
-This drops you straight into opencode with your project mounted at `/workspace`. Use `bash` as the command (e.g. `docker compose run --rm devbox bash`) to land in a shell first — useful for `aws sso login` or multi-agent workflows.
+This mounts your project at `/workspace`. With no command (as above) the image's default `CMD` (`bash -l`) drops you into a login shell — run `opencode` to start the harness, or `aws sso login` first, etc. To start opencode directly, pass it as the command: `docker compose run --rm devbox opencode`.
 
 **One-shot run, no persistence:**
 

README.md

@@ -27,7 +27,7 @@ $EDITOR .env
 docker compose run --rm devbox
 ```
 
-This pulls `joakimp/opencode-devbox:latest` from Docker Hub, mounts `WORKSPACE_PATH` at `/workspace`, and drops you straight into opencode. Use `bash` instead of (no command) to land in a shell first — useful for `aws sso login`, `omos`, etc.
+This pulls `joakimp/opencode-devbox:latest` from Docker Hub and mounts `WORKSPACE_PATH` at `/workspace`. With no command (as above) the image's default `CMD` (`bash -l`) drops you into a **login shell** — from there run `opencode` to start the harness, or do `aws sso login` first, launch `omos`, etc. To start opencode directly and skip the shell, pass it as the command: `docker compose run --rm devbox opencode`.
 
 **Want to hack on the image itself, follow upstream changes, or rebuild from source?** Clone the repo:
 

scripts/generate-dockerhub-md.py

@@ -88,7 +88,7 @@ curl -fsSL https://gitea.jordbo.se/joakimp/opencode-devbox/raw/branch/main/.env.
 docker compose run --rm devbox
 ```
 
-This drops you straight into opencode with your project mounted at `/workspace`. Use `bash` as the command (e.g. `docker compose run --rm devbox bash`) to land in a shell first — useful for `aws sso login` or multi-agent workflows.
+This mounts your project at `/workspace`. With no command (as above) the image's default `CMD` (`bash -l`) drops you into a login shell — run `opencode` to start the harness, or `aws sso login` first, etc. To start opencode directly, pass it as the command: `docker compose run --rm devbox opencode`.
 
 **One-shot run, no persistence:**