Claude Code 2.1.179: Partial Responses Preserved After Mid-Stream Connection Drops
Claude CodeClaude Code version 2.1.179, released June 16, 2026, addresses one of the tool's most widely reported reliability issues: mid-stream connection drops that previously caused in-progress responses to vanish entirely. Claude Code now preserves partial responses during disconnections instead of surfacing a raw error, preventing users from losing work mid-turn. The release also resolves a mouse-wheel scrolling regression in WSL2 and fixes a Linux sandbox glob pattern issue that could render sessions unusable on large directory trees.
Key Takeaways
- Partial responses are now preserved on mid-stream drops, preventing the total loss of in-progress model output that previously forced users to re-run entire sessions from scratch.
- The "stream idle timeout" error was one of the most-reported bugs in Claude Code, with dozens of GitHub issues citing it as a critical reliability failure — especially during long tool-use turns and large file writes.
- Users previously had no recovery path when a connection dropped mid-response; the work simply vanished, creating a compounding cost in token usage and time on complex tasks.
- WSL2 mouse-wheel scrolling is restored after a regression in 2.1.172 broke scroll input for users running Claude Code inside Windows Terminal or VS Code on Windows Subsystem for Linux.
- Linux users with large codebases were hit by a separate session-breaking bug where sandbox glob patterns caused the Bash tool description to expand to an unworkable size, making sessions unusable.
- The release is otherwise a maintenance release, with multiple minor UX fixes (welcome screen banners, feedback survey ratings, Ctrl+O subagent transcript access) that polish the day-to-day experience.
Sources & Mentions
5 external resources covering this update
[BUG] Stream idle timeout / partial response received on Claude Code Web
GitHub
[FEATURE] Streaming Resilience: Detect network loss, save in-flight state, and auto-resume on reconnect
GitHub
How I Stopped Getting "Stream Idle Timeout" Errors in Claude Code
Dev.to
[BUG] Persistent mid-stream ECONNRESET on large-context sessions
GitHub
Claude Code Updates by Anthropic — June 2026
Releasebot
A Long-Standing Pain Point Finally Fixed
One of the most frustrating experiences for Claude Code users over recent months has been the "API Error: Stream idle timeout — partial response received" message: the model would be mid-response, the connection would drop, and the partial output would disappear entirely, replaced by a cryptic error. Users had no way to recover the in-progress work and had to re-run their entire request from scratch.
Version 2.1.179 directly addresses this. Claude Code now preserves partial responses during mid-stream connection drops rather than discarding them and showing a raw error. This change means that when a connection is interrupted — due to network instability, VPN reconnects, sleep/wake cycles, or API backend hiccups — whatever the model had already produced is retained and displayed, rather than lost.
The stream idle timeout issue was among the most reported bugs on the Claude Code GitHub repository throughout early-to-mid 2026, with multiple issues filed specifically naming long tool-use turns, large file writes, and Opus 4.7 sessions as triggers. This fix closes a significant gap in session reliability.
Additional Fixes in 2.1.179
WSL2 Mouse-Wheel Scrolling Restored
A scrolling regression introduced in version 2.1.172 broke mouse-wheel input in WSL2 environments running under Windows Terminal and VS Code. Version 2.1.179 restores correct scroll behavior for these users.
Linux Sandbox Glob Patterns
On Linux systems with large directory trees, malformed sandbox denyRead/allowRead glob patterns could cause the Bash tool description to balloon to an enormous size, effectively making sessions unusable. This release resolves the issue.
Minor Reliability Improvements
Several smaller fixes ship alongside the headline changes: the feedback survey no longer misinterprets single-digit replies as session ratings, the welcome screen no longer stacks multiple promotional banners simultaneously, Ctrl+O now correctly opens subagent transcripts, prompt input focus returns properly after subagent and footer panel interactions, and remote session background task status updates more accurately between turns.