Tool calls issues on Windows — page 2
Issues the maintainers labelled both platform:windows and area:tools.
891 issues · 119 open · 772 resolved (87%) · first seen May 20, 2025
Is this getting better or worse?
This class of problem is holding steady. 153 new reports in the last 90 days vs 198 in the 90 before — -23%. The open backlog peaked at 193 in 2026-01 and sits at 119 today.
Derived by counting each matching issue from its creation date until it closed. First-party
computation over the anthropics/claude-code tracker — the trend is not published
anywhere upstream.
Which builds report this
387 of these reports name the Claude Code build they were running, spanning 137 releases. Heaviest reporters:
- Claude Code v2.0.76
- Claude Code v2.1.19
- Claude Code v2.1.12
- Claude Code v2.1.119
- Claude Code v2.1.71
- Claude Code v2.1.29
- Claude Code v2.1.23
- Claude Code v2.1.123
Report volume, not a defect count: an issue can mention a build without that build having caused the failure. Versions come from the version string in the bug-report template, matched against real published tags.
Do these get fixed?
Median time to close is 35 days across 772 closures. Of the 772 closures with a recorded reason, 24% were closed as completed and 587 as not-planned or duplicate. The most recent completed fix landed in 2026-08.
Workarounds reported by the community
343 of these issues post a workaround someone says worked. The highest-engagement ones:
- [BUG] file named nul created on windows
- …a regular filename, bypassing Windows reserved name checks. Workaround for users: If you encounter this issue, use Git Bash to remove the file:
Found in the thread of #4928 · resolved - [Feature Request] Claude Desktop: Option to execute commands in WSL instead of Windows
- …ommands, extensions, and file operations happen inside WSL. Workaround (Current) Running Claude Code CLI directly inside WSL terminal works perfectly, but loses the benefits of Claude Desktop's UI and extended context. A…
Found in the description of #12506 · resolved - [Bug] Anthropic API Error: Tool Use Concurrency Limitation
- I tried many workaround without success. In my case, it was a specific PDF file causing the issue. Once unreferenced, it works.
Found in the thread of #9002 · resolved - [BUG] creates `tmpclaude-*-cwd` files in the current working directory
- …ject's working directory regardless of the env var setting. Workaround: Adding to hides them from git status, but doesn't prevent their creation in the project directory.
Found in the thread of #17600 · resolved - Claude in Chrome extension not connecting despite being installed and enabled
- ✅ Workaround Confirmed Working (Windows 11, Claude Code 2.1.29) Root cause identified by @kimchi-developer in 21791 — the function (socket path discovery) doesn't return Windows named pipe path. Quick Fix 1. Backup cli.j…
Found in the thread of #21371 · resolved
Excerpts are quoted from the linked issue so you can judge relevance before opening it. Threads that only ask for a workaround, or report that there is none, are excluded. These are community suggestions, not official guidance from Anthropic — read the full thread before applying one.
Matching issues 101–200
Ranked by community engagement (reactions weighted over comments). Listing the top 300 of 891 matches; the statistics above cover all 891.
- [BUG] TodoWrite re-stamps a front-of-context block on every update, invalidating the entire prompt cache (full ~900k-token rewrite per todo update)
- Opus 4.8 (1M context) — frequent "tool_use malformed" client errors despite tools executing successfully
- [BUG] aude in Chrome browser extension not connecting from Claude Code on Windows despite correct configuration
- tmpclaude-*-cwd temp files created in working directory instead of system temp
- [FEATURE] Enable Task tool for subagents with configurable depth limit
- /plugin marketplace add rejects official anthropics/life-sciences repository with "reserved name" error
- [BUG] Could not process image
- [BUG] Haiku agents do not work if MAX_THINKING_TOKENS is set.
- Edit tool broken: 'replace_all type is expected as boolean but provided as string'
- [BUG] Streaming text disappears entirely when followed by tool calls in same response
- Windows: yarn/npm commands produce no output in Bash tool
- [BUG] Bash onecmd option causes npm script output to be lost on Windows
- Plugin hooks cannot execute scripts on Windows - /bin/bash cannot resolve file paths
- [BUG] AskUserQuestion tool not available to subagents regardless of configuration
- [BUG] # Critical Bug: Background Bash Processes Cause Infinite System-Reminders and Token Exhaustion
- Agent Creation Fails: Saved Agents Not Detected in CLI Listing
- [BUG] bug in Claude Code's PDF parser
- PostToolUse hooks with additionalContext not surfacing for MCP tool calls
- [BUG] Browser extension shows "Enabled/Installed" but tools report "not connected"
- API Error: 400 due to tool use concurrency issues when reading multiple files
- [BUG] API Error 400 "tool use concurrency issues" on every tool call in VSCode extension
- [BUG] run_in_background=true Task agents silently lose all output unless Write tool explicitly called
- [BUG] Edit tool strips trailing spaces in Markdown files
- [BUG] can not add marketplace on windows
- [BUG] Typing /context adds 2000 tokens to the context
- Filesystem Path Resolution Error in Claude Code CLI
- [QUESTION] Conda environment workflow guidance needed - inherited environment but missing shell functions
- PowerShell tool fails with exit code 1 on Windows when pwsh installed via winget
- [BUG] Claude Code on Windows does not know its on windows, nor remember and apply rules in memory.md to do with the user's preferences with CR/LF. It's a bad boy on windows.
- [BUG] Bash tool produces no output on Windows - commands run but output files remain empty
- [BUG] Getting "No task found with ID" from subagent
- [BUG] JavaScript heap exhaustion (OOM crash) during heavy Task tool/agent usage
- [BUG] LSP plugins not loading servers on Windows - "No LSP server available for file type"
- [BUG] Skill tool fails to activate plugin-dev skills - missing build.sh script
- [Bug] Anthropic API Error: Tool Use IDs Without Tool Result Blocks When Parsing PDFs
- [Bug] Anthropic API Error: Incomplete Tool Invocation Response
- [BUG] API Error 400: "Image format image/png not supported" — Claude Code auto-generated screenshots rejected
- [Bug] Output token limit settings not being applied, agent output capped at 32k tokens
- [BUG] Claude Code corrupts accented characters (ISO-8859-1 encoding issue)
- [Bug] CLI Incorrectly Defaults to UNIX Commands on Windows 11
- [Bug] Persistent Read Permissions Prompt and Auto-Edit Functionality Failure
- Bug: `SendUserFile` reports success but delivers nothing (VS Code extension)
- [Bug] Windows: terminal/cmd windows flash on every subprocess spawn across multiple CCD sessions
- [BUG] Read tool (Claude Code Desktop): optional `pages` sent as "" fails validation on non-PDF
- Read tool returns incorrect image content for PNG files (rendering routed to wrong file / permuted across batch)
- AskUserQuestion auto-completes with empty answers in v2.1.104 (regression from v2.1.101)
- [BUG] Edit Tool Unicode-to-ASCII Mojibake Corruption on Windows (.md files)
- [BUG] Windows: Chrome extension native host crashes with EADDRINUSE pipe conflict
- [BUG] orphaned processes from subagents crashing computer
- [BUG] Bash tool leaves tmpclaude-*-cwd files uncleaned on Windows/Git Bash
- [Question] Edit tool: Diff view only opens for single-line edits, not multi-line - is this by design?
- [BUG] WebFetch tool unable to access any external documentation sites
- [Bug] File Modification Error During Update Operation
- [Bug] Persistent Permission Prompts During Code Acceptance
- [BUG] Claude Code self-approves under plan mode
- InputValidationError: long unicode-escaped tool arguments fail JSON parse (AskUserQuestion) — retry with shorter input succeeds
- [BUG] constant permission requests and preference of Bash() calls over built-in tools
- AskUserQuestion Tool Regression with --dangerously-skip-permissions
- [BUG] Claude Cowork for Windows, plugin skills searched at wrong location
- Chrome extension not connecting to Claude Code via native messaging on Windows 11
- [BUG] Bash tool produces no output when executing scripts on Windows/MSYS2
- Hooks don't receive tool input for Read/Glob; permission patterns don't match tilde paths
- [Feature Request] Add environment variable to identify CLI shell type (Bash/PowerShell/CMD)
- [BUG] Claude Code no longer inherits conda environment from VSCode terminal after UI update
- Read tool PDF support broken on Windows — sandbox rejects pdftoppm from all locations
- [BUG] AskUserQuestion: partial submit discards all already-provided answers
- Edit tool corrupts non-ASCII Unicode characters (typographic quotes) in string literals
- [BUG] Task tool subagents spawn duplicate MCP servers and leak ~/.claude/tasks/ directories on Windows
- [BUG] Grep tool completely non-functional on Windows ARM64 — ripgrep arm64-win32 binary injects its own path as regex pattern
- [BUG] Background task completion notification not appearing / activating Claude
- [BUG] API Error 400 'tool use concurrency issues' in VSCode extension on simple operations
- [BUG] This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch().
- [BUG] file search is not working like before in v2.0.74
- Skill tool incorrectly parses markdown content as shell commands
- [BUG] [platform:windows] git-bash -> bash: /c: Is a directory Exit 126
- [BUG] Windows + Git Bash: tengu_cobalt_ridge experiment silently force-enables the PowerShell tool & "Shell: PowerShell", causing wrong-shell retries (token waste)
- EEXIST: file already exists, mkdir when Edit tool updates files in existing directories on Windows
- [FEATURE] Write tool should respect .editorconfig / .gitattributes line ending settings (LF vs CRLF)
- [BUG] Chrome MCP tools never load in VS Code — claude-vscode MCP fails with -32601: Method not found (Windows 11)
- [Bug] Sibling tool call errored regression since v2.1.19
- Windows: ${CLAUDE_PLUGIN_ROOT} backslashes stripped when passed to bash hooks
- Chrome extension not connecting on Windows 11 (Build 26200)
- Edit tool fails with 'File has been unexpectedly modified' immediately after Read
- [BUG] ${CLAUDE_PLUGIN_ROOT} portability
- [BUG] Custom slash commands no longer working
- [BUG] Read/Edit tracker is case-sensitive on Windows; drive-letter casing mismatch triggers "File has not been read yet"
- Scheduled tasks and background sub-agents leak processes/UI state without cleanup
- [BUG] Claude Code for VS Code 2.1.117: Read/Edit tools fail on Windows when username contains \uXXXX sequence
- [Bug] Claude does not verify file edits applied correctly — blind edit-and-proceed
- [BUG] Claude in Chrome MCP shows "connected" but tools return "Browser extension is not connected"
- API Error: thinking blocks cannot be modified during Write operations
- Plugins from third-party marketplaces don't appear in /plugin list
- Feature request: non-blocking tasks / notification to main agent when a background bash session finishes
- Search Tool Returns Zero Results on Windows Platform
- Read tool reports "pdftoppm is not installed" on Windows despite poppler being on PATH
- Read tool renders JS Unicode escape sequences inconsistently, causing Edit failures
- [BUG] Edit Tool Fails with 'File unexpectedly modified' on Windows (Access Time Update Issue)
- Documentation update for security. Claude overrides rules but this is not obvious and only reveals it after pain. Update documentation giving abstraction solution PLEASE
- [BUG] Critical Bug - Claude Code forces non-existent cygpath on Windows, ignoring available shells
- Agent Discovery Failure: Generated Agents Not Recognized or Loadable