mini-swe-agent vs OpenCode

mini-swe-agent

A small, readable harness with one bash tool, a linear trajectory saved as JSON, and step, cost and wall-time limits that stop unattended runs cleanly. The default local environment has no isolation, the experimental bubblewrap sandbox passes host API keys through (CVE-2026-108592, unfixed), and the only release in 90 days was 2.4.6 on 23 July 2026.

OpenCode

Runs with no key or account on free OpenCode Zen models. Most permissions default to allow, and SECURITY.md says the permission system is not a sandbox.

mini-swe-agent

1. Run with -y --exit-immediately for unattended use. Without --exit-immediately it waits for input when the agent finishes
2. Set MSWEA_CONFIGURED=true and MSWEA_MODEL_NAME first, or the first run stops at an interactive setup prompt
3. Read info.exit_status in the -o trajectory file. A run that hits its limits still exits normally
4. For untrusted repositories use -c mini.yaml -c environment.environment_class=docker -c environment.image=<image>. The local and bubblewrap environments both expose host variables
5. Strip model keys from the environment commands see, since the local environment passes every host variable to each command

OpenCode

1. Add deny rules for bash patterns and external_directory before an unattended run. Most tools default to allow
2. Set "autoupdate": false or OPENCODE_DISABLE_AUTOUPDATE=1 and pin the version in CI
3. Configure a provider key. With none, prompts go to free Zen models that may train on them
4. Set OPENCODE_SERVER_PASSWORD before opencode serve. Without it the server runs unauthenticated
5. Install opencode-ai for the 1.x server API and SDK. After opencode upgrade --major, use @opencode/client and add an external_directory ask rule