Cowork runaway task — agent runs 4+ hours without self-terminating, UI timer active but no meaningful progress
Resolved 💬 1 comment Opened Apr 22, 2026 by JeanLucBrausch Closed May 29, 2026
Preflight Checklist
- [x] I have searched existing issues and this hasn't been reported yet
- [x] This is a single bug report (please file separate reports for different bugs)
- [x] I am using the latest version of Claude Code
What's Wrong?
Claude Desktop version: latest
Plan: Max
Connectors enabled: Gmail
Summary
Two distinct failure modes observed in one session on Cowork:
Silent freeze (matches #26646): Task "Extract forensic notes from confidential emails" hung for 90+ minutes. VM bundle grew to 20GB. rootfs.img and sessiondata.img timestamps showed zero filesystem activity for 90+ minutes while UI continued to display "Working through a complex response..." with an incrementing timer.
Runaway agent (new, not covered by existing issues): After wiping ~/Library/Application Support/Claude/vm_bundles/ and restarting with a fresh VM, the same task ran for 277 minutes (4h 37m) without self-terminating. During this period rootfs.img was being actively written (timestamps current), but sessiondata.img had not been updated for 4+ hours, suggesting the agent was looping internally without checkpointing.
What Should Happen?
Reproduction
Open Cowork, create task: "Extract forensic notes from confidential emails"
Enable Gmail connector
Submit task with no explicit runtime bound
Observe: agent runs indefinitely, UI provides no tool-call visibility, no cost/time warnings
Diagnostic evidence
Bundle size progression: ~3GB (fresh) → 20GB (frozen state) → wipe → 9.8GB (runaway state)
ls -lat output showing divergent timestamps on rootfs.img (current) vs sessiondata.img (stale 4h+)
[Attach screenshots of 277m timer]
Expected behavior
Agent should self-terminate, checkpoint, and request continuation after a reasonable duration
UI should show what tool calls are being made (e.g., "Reading email 47 of N")
Time/cost thresholds should trigger user prompts ("task has been running 30m, continue/stop/refine?")
Additional observations
warm/ template-based recovery worked cleanly (nuking claudevm.bundle while preserving warm/ gave a fast, clean reset) — worth documenting as a supported workaround
Tasks involving connectors with effectively unbounded data sources (Gmail, Drive) appear particularly prone to runaway behavior
Offered to share session logs with Anthropic support for deeper diagnosis
Error Messages/Logs
total 400
-rw-r--r--@ 1 schluck staff 48 Feb 4 17:54 ant-did
drwx------@ 7 schluck staff 224 Feb 4 17:54 Crashpad
drwx------@ 4 schluck staff 128 Feb 4 17:54 Cache
drwx------@ 4 schluck staff 128 Feb 4 17:54 Code Cache
drwx------@ 7 schluck staff 224 Feb 4 17:54 GPUCache
drwx------@ 7 schluck staff 224 Feb 4 17:54 DawnWebGPUCache
drwx------@ 7 schluck staff 224 Feb 4 17:54 DawnGraphiteCache
drwx------@ 5 schluck staff 160 Feb 4 17:54 Shared Dictionary
-rw-------@ 1 schluck staff 36864 Feb 4 17:54 Trust Tokens
-rw-------@ 1 schluck staff 0 Feb 4 17:54 Trust Tokens-journal
-rw-------@ 1 schluck staff 4096 Feb 4 17:56 SharedStorage
drwxr-xr-x@ 3 schluck staff 96 Feb 4 18:14 claude-code-sessions
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 vm_bundles
drwxr-xr-x@ 4 schluck staff 128 Feb 18 12:33 local-agent-mode-sessions
drwx------@ 4 schluck staff 128 Apr 7 12:54 IndexedDB
drwxr-xr-x@ 3 schluck staff 96 Apr 7 13:50 Claude Extensions Settings
-rw-r--r--@ 1 schluck staff 8020 Apr 7 13:50 extensions-installations.json
-rw-------@ 1 schluck staff 7815 Apr 9 11:13 .com.anthropic.claudefordesktop.L28w3T
-rw-------@ 1 schluck staff 0 Apr 9 11:13 .com.anthropic.claudefordesktop.AUofWM
drwxr-xr-x@ 16 schluck staff 512 Apr 9 14:24 pending-uploads
drwx------@ 4 schluck staff 128 Apr 10 11:30 VideoDecodeStats
drwx------@ 8 schluck staff 256 Apr 10 11:30 shared_proto_db
drwxr-xr-x@ 3 schluck staff 96 Apr 17 03:55 Claude Extensions
drwx------@ 4 schluck staff 128 Apr 17 19:30 Partitions
drwxr-xr-x@ 3 schluck staff 96 Apr 17 19:31 claude-code
drwxr-xr-x@ 4 schluck staff 128 Apr 17 19:31 claude-code-vm
drwx------@ 4 schluck staff 128 Apr 20 14:29 WebStorage
drwx------+ 127 schluck staff 4064 Apr 21 07:05 ..
drwx------@ 3 schluck staff 96 Apr 21 13:52 Local Storage
-rw-------@ 1 schluck staff 0 Apr 21 13:56 .com.anthropic.claudefordesktop.14CEHU
-rw-------@ 1 schluck staff 5596 Apr 22 09:05 git-worktrees.json
drwx------@ 3 schluck staff 96 Apr 22 13:01 blob_storage
drwx------@ 12 schluck staff 384 Apr 22 13:01 Session Storage
-rw-------@ 1 schluck staff 61 Apr 22 13:01 cowork-enabled-cli-ops.json
-rw-------@ 1 schluck staff 177 Apr 22 13:01 extensions-blocklist.json
-rw-------@ 1 schluck staff 350 Apr 22 13:01 bridge-state.json
-rw-------@ 1 schluck staff 68 Apr 22 13:06 buddy-tokens.json
-rw-------@ 1 schluck staff 14309 Apr 22 13:10 fcache
-rw-------@ 1 schluck staff 245 Apr 22 13:12 claude_desktop_config.json
-rw-r--r--@ 1 schluck staff 2484 Apr 22 13:38 config.json
-rw-------@ 1 schluck staff 217 Apr 22 13:49 Preferences
-rw-r--r--@ 1 schluck staff 141 Apr 22 13:49 window-state.json
drwxr-xr-x@ 4 schluck staff 128 Apr 22 13:49 sentry
-rw-------@ 1 schluck staff 36864 Apr 22 13:49 DIPS
-rw-------@ 1 schluck staff 6196 Apr 22 13:49 TransportSecurity
-rw-------@ 1 schluck staff 7581 Apr 22 13:49 Network Persistent State
drwx------@ 49 schluck staff 1568 Apr 22 13:49 .
-rw-------@ 1 schluck staff 32768 Apr 22 13:49 Cookies
-rw-------@ 1 schluck staff 0 Apr 22 13:49 Cookies-journal
Mac:Claude root# cd vm_bundles/
claudevm.bundle/ warm/
Mac:Claude root# cd vm_bundles/
Mac:vm_bundles root# ls
claudevm.bundle warm
Mac:vm_bundles root# ls -lart
total 0
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 .
drwxr-xr-x@ 3 schluck staff 96 Mar 31 08:21 warm
drwxr-xr-x@ 12 schluck staff 384 Apr 22 13:01 claudevm.bundle
drwx------@ 49 schluck staff 1568 Apr 22 13:49 ..
Mac:vm_bundles root# cd warm
Mac:warm root# ls
5680b11bcdab215cccf07e0c0bd1bd9213b0c25d
Mac:warm root# ls -la
total 0
drwxr-xr-x@ 3 schluck staff 96 Mar 31 08:21 .
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 ..
drwxr-xr-x@ 2 schluck staff 64 Mar 31 08:39 5680b11bcdab215cccf07e0c0bd1bd9213b0c25d
Mac:warm root# cd ..
Mac:vm_bundles root# ls -lart
total 0
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 .
drwxr-xr-x@ 3 schluck staff 96 Mar 31 08:21 warm
drwxr-xr-x@ 12 schluck staff 384 Apr 22 13:01 claudevm.bundle
drwx------@ 49 schluck staff 1568 Apr 22 13:49 ..
Mac:vm_bundles root# cd claudevm.bundle/
Mac:claudevm.bundle root# LW
-sh: LW: command not found
Mac:claudevm.bundle root# ls
.rootfs.img.origin macAddress sessiondata.img
.rootfs.img.zst.origin machineIdentifier vmIP
efivars.fd rootfs.img
gvisorMacAddress rootfs.img.zst
Mac:claudevm.bundle root# ls -la
total 40946864
drwxr-xr-x@ 12 schluck staff 384 Apr 22 13:01 .
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 ..
-rw-r--r--@ 1 schluck staff 40 Apr 1 11:49 .rootfs.img.origin
-rw-r--r--@ 1 schluck staff 40 Apr 1 11:49 .rootfs.img.zst.origin
-rw-------@ 1 schluck staff 131072 Apr 22 13:01 efivars.fd
-rw-r--r--@ 1 schluck staff 17 Apr 7 12:54 gvisorMacAddress
-rw-r--r--@ 1 schluck staff 17 Feb 4 18:01 macAddress
-rw-r--r--@ 1 schluck staff 70 Feb 4 18:01 machineIdentifier
-rw-r--r--@ 1 schluck staff 10737418240 Apr 22 13:49 rootfs.img
-rw-r--r--@ 1 schluck staff 2200840699 Apr 1 11:49 rootfs.img.zst
-rw-r--r--@ 1 schluck staff 10327613440 Apr 22 13:49 sessiondata.img
-rw-r--r--@ 1 schluck staff 11 Apr 22 13:01 vmIP
Mac:claudevm.bundle root# rm -f *
Mac:claudevm.bundle root# ls
.rootfs.img.origin .rootfs.img.zst.origin
Mac:claudevm.bundle root# ls -lart
total 24911656
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 ..
-rw-------@ 1 schluck staff 2200840699 Apr 22 13:54 rootfs.img.zst
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.origin
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.zst.origin
-rw-r--r--@ 1 schluck staff 70 Apr 22 13:54 machineIdentifier
-rw-------@ 1 schluck staff 131072 Apr 22 13:54 efivars.fd
-rw-r--r--@ 1 schluck staff 17 Apr 22 13:54 gvisorMacAddress
-rw-r--r--@ 1 schluck staff 11 Apr 22 13:55 vmIP
drwx------@ 11 schluck staff 352 Apr 22 13:55 .
-rw-r--r--@ 1 schluck staff 209633280 Apr 22 13:55 sessiondata.img
-rw-------@ 1 schluck staff 10737418240 Apr 22 13:55 rootfs.img
Mac:claudevm.bundle root# ls -lart
total 25005664
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 ..
-rw-------@ 1 schluck staff 2200840699 Apr 22 13:54 rootfs.img.zst
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.origin
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.zst.origin
-rw-r--r--@ 1 schluck staff 70 Apr 22 13:54 machineIdentifier
-rw-------@ 1 schluck staff 131072 Apr 22 13:54 efivars.fd
-rw-r--r--@ 1 schluck staff 17 Apr 22 13:54 gvisorMacAddress
-rw-r--r--@ 1 schluck staff 11 Apr 22 13:55 vmIP
drwx------@ 11 schluck staff 352 Apr 22 13:55 .
-rw-r--r--@ 1 schluck staff 254341120 Apr 22 13:55 sessiondata.img
-rw-------@ 1 schluck staff 10737418240 Apr 22 13:56 rootfs.img
Mac:claudevm.bundle root# ls -lart
total 25005664
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 ..
-rw-------@ 1 schluck staff 2200840699 Apr 22 13:54 rootfs.img.zst
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.origin
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.zst.origin
-rw-r--r--@ 1 schluck staff 70 Apr 22 13:54 machineIdentifier
-rw-------@ 1 schluck staff 131072 Apr 22 13:54 efivars.fd
-rw-r--r--@ 1 schluck staff 17 Apr 22 13:54 gvisorMacAddress
-rw-r--r--@ 1 schluck staff 11 Apr 22 13:55 vmIP
drwx------@ 11 schluck staff 352 Apr 22 13:55 .
-rw-r--r--@ 1 schluck staff 254341120 Apr 22 13:55 sessiondata.img
-rw-------@ 1 schluck staff 10737418240 Apr 22 13:56 rootfs.img
Mac:claudevm.bundle root# ls -lart
total 24978016
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 ..
-rw-------@ 1 schluck staff 2200840699 Apr 22 13:54 rootfs.img.zst
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.origin
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.zst.origin
-rw-r--r--@ 1 schluck staff 70 Apr 22 13:54 machineIdentifier
-rw-------@ 1 schluck staff 131072 Apr 22 13:54 efivars.fd
-rw-r--r--@ 1 schluck staff 17 Apr 22 13:54 gvisorMacAddress
-rw-r--r--@ 1 schluck staff 11 Apr 22 13:55 vmIP
drwx------@ 11 schluck staff 352 Apr 22 13:55 .
-rw-r--r--@ 1 schluck staff 254341120 Apr 22 13:55 sessiondata.img
-rw-------@ 1 schluck staff 10737418240 Apr 22 14:00 rootfs.img
Mac:claudevm.bundle root# ls -lart
total 24977928
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 ..
-rw-------@ 1 schluck staff 2200840699 Apr 22 13:54 rootfs.img.zst
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.origin
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.zst.origin
-rw-r--r--@ 1 schluck staff 70 Apr 22 13:54 machineIdentifier
-rw-------@ 1 schluck staff 131072 Apr 22 13:54 efivars.fd
-rw-r--r--@ 1 schluck staff 17 Apr 22 13:54 gvisorMacAddress
-rw-r--r--@ 1 schluck staff 11 Apr 22 13:55 vmIP
drwx------@ 11 schluck staff 352 Apr 22 13:55 .
-rw-------@ 1 schluck staff 10737418240 Apr 22 14:05 rootfs.img
-rw-r--r--@ 1 schluck staff 254341120 Apr 22 14:05 sessiondata.img
Mac:claudevm.bundle root# ls -lart
total 20478296
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 ..
-rw-------@ 1 schluck staff 2200840699 Apr 22 13:54 rootfs.img.zst
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.origin
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.zst.origin
-rw-r--r--@ 1 schluck staff 70 Apr 22 13:54 machineIdentifier
-rw-------@ 1 schluck staff 131072 Apr 22 13:54 efivars.fd
-rw-r--r--@ 1 schluck staff 17 Apr 22 13:54 gvisorMacAddress
-rw-r--r--@ 1 schluck staff 11 Apr 22 13:55 vmIP
drwx------@ 11 schluck staff 352 Apr 22 13:55 .
-rw-r--r--@ 1 schluck staff 254341120 Apr 22 14:05 sessiondata.img
-rw-------@ 1 schluck staff 10737418240 Apr 22 18:22 rootfs.img
Mac:claudevm.bundle root# du -sh /Users/schluck/Library/Application\ Support/Claude/vm_bundles/
9.8G /Users/schluck/Library/Application Support/Claude/vm_bundles/
Mac:claudevm.bundle root# ls -lart
total 20478296
drwxr-xr-x@ 4 schluck staff 128 Feb 13 11:24 ..
-rw-------@ 1 schluck staff 2200840699 Apr 22 13:54 rootfs.img.zst
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.origin
-rw-------@ 1 schluck staff 40 Apr 22 13:54 .rootfs.img.zst.origin
-rw-r--r--@ 1 schluck staff 70 Apr 22 13:54 machineIdentifier
-rw-------@ 1 schluck staff 131072 Apr 22 13:54 efivars.fd
-rw-r--r--@ 1 schluck staff 17 Apr 22 13:54 gvisorMacAddress
-rw-r--r--@ 1 schluck staff 11 Apr 22 13:55 vmIP
drwx------@ 11 schluck staff 352 Apr 22 13:55 .
-rw-r--r--@ 1 schluck staff 254341120 Apr 22 14:05 sessiondata.img
-rw-------@ 1 schluck staff 10737418240 Apr 22 18:22 rootfs.img
Mac:claudevm.bundle root# laude --version and paste the output
-sh: laude: command not found
Mac:claudevm.bundle root# claude --version and paste the output
2.1.92 (Claude Code)Steps to Reproduce
Open Cowork, create task: "Extract forensic notes from confidential emails"
Enable Gmail connector
Submit task with no explicit runtime bound
Observe: agent runs indefinitely, UI provides no tool-call visibility, no cost/time warnings
Claude Model
Not sure / Multiple models
Is this a regression?
I don't know
Last Working Version
no idea
Claude Code Version
2.1.92 (Claude Code)
Platform
Anthropic API
Operating System
macOS
Terminal/Shell
Terminal.app (macOS)
Additional Information
Also worth filing this on the GitHub issue thread (#26646) — your 20GB number is a useful data point beyond what's already reported, and Anthropic engineers track that issue.
This issue has 1 comment on GitHub. Read the full discussion on GitHub ↗