Three Claude Code Week 26 Upgrades Worth Knowing: Shell MCP Auth, Rewind Past /clear, Background Prompt Relay

TL;DR: Claude Code Week 26 ships MCP shell auth, /rewind past /clear, and background agent permission prompts that reach you instead of silently dying — update to v2.1.185+.

Three Week 26 (June 22–26) changes that fix real papercuts in multi-agent and MCP workflows:

claude mcp login <server-name> — authenticate a configured MCP server directly from your shell instead of navigating the interactive /mcp menu. Clear stored credentials later with claude mcp logout. Useful when scripting environment setup or onboarding teammates.

/rewind now reaches past /clear — previously, clearing context was permanent within a session. You can now open the rewind menu after /clear and step back to before it ran, recovering both the conversation and the file state at that checkpoint.

Background subagents relay permission prompts — instead of auto-denying and failing silently, background agents now surface permission prompts in your main session. Long overnight runs that hit an unexpected file write or shell command will pause and ask rather than halt with a cryptic error.

Why it matters: These three changes together make multi-session, background-agent workflows substantially more reliable. A background task that hits a prompt no longer silently fails; a context clear is no longer irreversible; and MCP setup is one command instead of a menu hunt.

Sources: Claude Code what's new — Week 26 | Claude Code changelog