Where does the bug appear (feature/product)?
Cursor IDE
Describe the Bug
Product: Cursor
Version: 3.13.10
OS: Windows 10/11 (NT 10.0.26200.0)
Tool: cursor-app-control MCP → move_agent_to_root
Also fails with: move_agent_to_cloned_root (same Missing blob error)
Summary
Calling move_agent_to_root to move an existing agent conversation from one folder to another fails every time with a Missing blob error. The failure is deterministic for this chat and blocks migrating the agent/workspace root while preserving conversation history.
Source workspace
L:\C-METRIC\www_c-imple_com
(mapped network drive / QNAP NAS: \nascmt\CMT_LSP...)
Target workspace
D:\CMT_Server\LSP\C-METRIC\www_c-imple_com
(local Qsync copy of the same project; folders are content-synced)
Conversation / project IDs
- Agent / conversation transcript ID: ec99a53e-551d-420a-88f1-030ad28a4052
- Cursor project folder: C:\Users\nunod.cursor\projects\l-C-METRIC-www-c-imple-com
- Missing blob hash: 7927f9406415ea2fc8012b0fdd87cb6e1501a2d227d0a0f724dd5d5c01871599
- Broken reference: conversationState.turns[690]:userMessageSelectedContext
Exact error (latest attempt)
Failed to move agent root: Missing blob while creating migration handle: 7927f9406415ea2fc8012b0fdd87cb6e1501a2d227d0a0f724dd5d5c01871599; referenceTypes=conversationState.turns[690]:userMessageSelectedContext; availableBlobCount=55913; stateBlobCounts={“rootTurnCount”:853,“rootPromptMessageCount”:305,“todoCount”:3,“summaryArchiveCount”:73,“summaryCount”:0,“planCount”:0,“fileStateCount”:0,“fileStateV2Count”:427,“fileStateV2ContentCount”:404,“fileStateV2InitialContentCount”:130,“subagentStateCount”:1}
Earlier identical failures (same blob + turn 690) also reported e.g.: - availableBlobCount around 55503–55873
- rootTurnCount around 839–850
- rootPromptMessageCount increasing over time
Always the same missing blob hash and always turns[690]:userMessageSelectedContext.
Steps to Reproduce
- Open a long-running Agent chat in workspace A (here: L:\C-METRIC\www_c-imple_com).
- At some earlier turn, select context in the UI (file/selection) that becomes userMessageSelectedContext.
- Later, from the agent, call cursor-app-control.move_agent_to_root with rootPath pointing to an existing local folder B that contains the same project (here: D:\CMT_Server\LSP\C-METRIC\www_c-imple_com).
- Observe immediate failure with Missing blob while creating migration handle.
Expected Behavior
Agent/chat migrates to the new workspace root and continues with the same conversation history.
Actual
Migration aborts. Workspace root does not change. Same failure on every retry, including move_agent_to_cloned_root.
Notes / investigation already done
- Source and target folders are synced (same source content; Qsync).
- Missing blob content is not present in:
- project files
- agent transcript JSONL
- %APPDATA%\Cursor\blob_storage (no file named with that hash)
- Blob hash string appears in Cursor state WAL (state.vscdb-wal) / transcripts as a reference only — payload is missing.
- This appears to be a corrupted/incomplete conversationState reference that permanently blocks migration for this chat.
Impact
Cannot move a long agent chat to a faster local workspace path while preserving history. Manual “Open Folder” loses active chat continuity (history remains on old workspace, but migration is impossible).
Request
Please either:
- allow migration to skip/drop unrecovered optional blobs such as userMessageSelectedContext, or
- provide a repair path to recreate/remove the broken blob reference so move_agent_to_root can succeed.
Operating System
Windows 10/11
Version Information
Version: 3.13.10 (user setup)
VS Code Extension API: 1.128.0
Commit: 4f02290ccd9304f0e6bf8ee85f6e9106f02ac1f0
Date: 2026-07-23T21:41:07.333Z
Layout: Agent Window
Build Type: Stable
Release Track: Default
Electron: 40.10.3
Chromium: 144.0.7559.236
Node.js: 24.15.0
V8: 14.4.258.32-electron.0
xterm.js: 6.1.0-beta.256
OS: Windows_NT x64 10.0.26200
For AI issues: which model did you use?
All
Does this stop you from using Cursor
No - Cursor works, but with this issue