DeepSeek Harness vs OpenCode
OpenCode ships a terminal, desktop and web shell with plugins and MCP; DeepSeek Harness composes its whole runtime from npm patch layers.
OpenCode is an open source coding agent with a TUI, a desktop app and a web interface reached through opencode pair. DeepSeek Harness has no desktop app; its surfaces are the terminal, dsh web, dsh headless, ACP and the SDK.
OpenCode installs from a shell script, Homebrew or npm, and the npm package runs a postinstall step to pick a native binary. DeepSeek Harness is plain npm and Node.js 24.9.0 or newer.
| DeepSeek Harness | OpenCode | |
|---|---|---|
| Install | npm install -g @deepseek-ai/dsh | curl -fsSL https://opencode.ai/v2/install | bash, Homebrew, npm or a standalone binary |
| Surfaces | Terminal, browser UI, headless, ACP, SDK | TUI, desktop app, web via opencode pair, Docker images |
| Extension unit | npm patch bundles and capability seams | Plugins, skills, commands, MCP servers |
| Config | package.json + cordis.patch.yml per profile, plus a home patch | A single OpenCode config |
| Session data | session*.jsonl.zstd under $DSH_HOME | Managed by OpenCode in its own storage |
| Windows | Supported; PowerShell executor and ACL sandbox backend available | Package managers on Windows are not supported; standalone binary is offered |
Pick DeepSeek Harness when
You want to own the runtime: replace the shell executor, swap the sandbox implementation, change how compaction works, and inspect the composed tree before booting.
Pick OpenCode when
You want a desktop app as well as a terminal, Docker images for reproducibility, and a config-file extension model rather than a patch-layer one.
The honest part
What DSH does worse: it is on release candidates, its documentation lives in the repository rather than a docs site, a plugin built for another dsh version is skipped at boot, and the plugin ecosystem is small. If you want a product with a support contract and a decade of tutorials, none of these three comparisons will talk you into DSH.
Common questions
Do both support MCP servers?
Yes. OpenCode documents MCP servers as first-class config; DSH reaches them through plugins in a profile.
Which one has more plugins today?
OpenCode's plugin list is larger right now. DSH publishes its seams as separate packages but the third-party ecosystem is smaller.
Does either need Docker?
No. OpenCode publishes Docker images for convenience; DSH runs directly from npm.