DeepSeek Harness adds custom plugin indexes in alpha.4

DeepSeek Harness alpha.4 adds discovery and installation from custom plugin indexes, alongside per-model reasoning settings in the interface. Plugin compatibility now prioritizes a declared engines.dsh version range. The update also improves failed-command status and reduces repeated Linux launch checks. This remains a prerelease: a compatible plugin version is not evidence that its code or publisher is trustworthy.

DeepSeek · Oct 15, 2026

Why it matters

This follow-up changes extension distribution and configuration rather than repeating the original agent launch.

More context

Try the release in an existing preview setup. Plugin authors should check engines.dsh declarations against supported Harness versions; older compatibility rules remain the fallback when it is absent.

Keep in mind

The release supplies no measured startup-speed result; compatibility metadata is not a security audit.

Original read