What changed
DeepSeek released Harness 0.2.2-rc.2 with named multi-level subagents, an optional AgentTeam panel and Git worktree review across branches, commits and file categories. It also switches default web search to DeepSeek Search, adds dynamic MCP service management and changes several plugin, sharing and computer-use interfaces.
Why it matters
The release candidate makes delegation and code review more inspectable while changing search, plugin and shared-session authority. Those migrations can improve control, but they can also silently alter which service, process or directory a session can reach.
What to do
Canary the RC in a disposable repository, delegate a nested task, review a synthetic branch and revoke one MCP service mid-run. Verify parent-child identity, task ownership, viewed-file state, search billing, worktree cleanup, shared-session access and rollback to the prior stable build.
Caveat
This is a release candidate with breaking migration notes, not a stable adoption boundary. DeepSeek provides maintainer evidence rather than an independent security or reliability assessment, and plugin, LiveShare and computer-use integrations may require coordinated upgrades.