The API layer issues on Windows — page 2
Issues the maintainers labelled both platform:windows and area:api.
400 issues · 32 open · 368 resolved (92%) · first seen Mar 2, 2025
Is this getting better or worse?
This class of problem is still growing. 97 new reports in the last 90 days vs 74 in the 90 before — +31%. The open backlog peaked at 90 in 2025-12 and sits at 32 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
197 of these reports name the Claude Code build they were running, spanning 65 releases. Heaviest reporters:
- Claude Code v2.1.114
- Claude Code v2.1.19
- Claude Code v2.1.29
- Claude Code v2.1.141
- Claude Code v2.1.76
- Claude Code v2.1.104
- Claude Code v2.1.56
- Claude Code v2.1.17
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 37 days across 368 closures. Of the 368 closures with a recorded reason, 24% were closed as completed and 279 as not-planned or duplicate. The most recent completed fix landed in 2026-06.
Workarounds reported by the community
47 of these issues post a workaround someone says worked. The highest-engagement ones:
- [Bug] VS Code extension: Tool use concurrency error after Jan 23-24 update
- ✅ WORKAROUND FOUND The fix: Install VS Code extension version 2.1.17 while keeping CLI at 2.1.19 Steps: 1. In VS Code, go to Extensions 2. Find "Claude Code for VS Code" 3. Click the dropdown arrow next to Uninstall → "I…
Found in the thread of #20571 · still open - [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] API Error: Rate limit reached despite Claude Max subscription and only 16% usage
- …nType: null and rateLimitTier: null. API credits were added as a workaround — they were consumed instantly (within seconds), leaving the account in debt. After fresh login subscription is recognized (subscriptionType: "m…
Found in the description of #29579 · still open - [BUG] Cowork Windows - Cannot connect to Claude API from workspace (Windows 11 Home)
- …same issue on Windows 11 Pro. Tried all of the recommended work-arounds and get the same result
Found in the thread of #24918 · resolved - [BUG] API Error: Server is temporarily limiting requests (not your usage limit) · Rate limited
- I have discovered a workaround - if you sign up for the GPT Codex Plan, you get a better coding agent and limits that are actually reflective of use. Solved my problem 100%.
Found in the thread of #53915 · still open
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 400 matches; the statistics above cover all 400.
- Feature request: auto-retry on API 500 errors
- API Error: 500 {"type":"error","error":{"type":"api_error","...
- [Bug] Missing Implementation: classifyHandoffIfNeeded Function
- [BUG] I am being blocked although I have usage remaining. See Details.
- You've hit your limit · resets 6pm (Asia/Bangkok)
- [BUG] tool_use ids must be unique error when making parallel tool calls (v2.1.19)
- [BUG] API Error 400: Tool use concurrency issues on all file operations
- API 500 Internal Server Error when reading PDF files
- [Bug] Anthropic API: Incorrect UTF-8 Encoding for German Umlauts - Model cheating!
- [Bug] Anthropic API Error: Internal Server Error
- [Bug] Model Performance Degradation Across Sessions
- Improve Error Messaging for API Usage Limits
- [BUG] Claude code returns 504 response from Claude Code
- [BUG] Usage limit being reached WAY TOO QUICKLY
- Anthropic API Timeout: Repeated Request Failures During Campaign Editor Initialization
- [BUG] Claude Code WSL2 Environment API Timeout Issue Report
- [BUG] Claude Code: Connection leak causing "offline" errors after 1-2 hours (WSL2)
- 2.1.141 regression: streaming stalls → sdk_stream_ended_no_result had_error:true on large conversations; 2.1.140 unaffected
- [Bug] Anthropic API Error: 503 Service Unavailable in createCodeSession endpoint
- [BUG] API Error 400
- [BUG] ENABLE_PROMPT_CACHING_1H is not working (API key user)
- [BUG] Claude code -API Error: Rate limit reached
- [Bug] Anthropic API Error: Internal Server Error (500)
- Repeated 500 Internal Server Errors on Claude Max plan (00/mo)
- API Error: 400 due to tool use concurrency issues - persists in specific project
- API Error 400: tool_use ids must be unique in --print mode (v2.1.19)
- [BUG] Claude Code Hangs with Next.js Dev Server + `run_in_background`
- [BUG] In Claude Code versions after 2.1.7, the input_tokens and output_tokens fields in the JSON are inaccurate
- [BUG] API Error: 400
- [BUG] Claude Code in VSCode expects model deployments from Azure Foundry in lowercase
- [Bug] Anthropic API Error: Image dimensions exceed max size on text-only prompts
- [BUG] console -api error. - invalid api --- even paste code on cluade code box, it still be invail api, what happen, lost 6 days has passed , even pay api payment- no support help, not any help from claude
- [Bug] Anthropic API Error: Server Overloaded (500)
- [BUG] CLI 401 OAuth errors. Multiple devices on two Pro accounts, fully paid.
- Missing Tool Result Block for Tool Use ID toolu_019aLkVUFjyvChUtaKKnfbm6
- [BUG] 502 error opus 4.8
- RemoteTrigger / Scheduled Tasks API returns 500 — cannot list, update, or delete triggers
- API Error 400: text content blocks must contain non-whitespace text
- [BUG] Extremely poor responsiveness to Australia
- [BUG] Error: API Error: 400 due to tool use concurrency issues
- [BUG] Could not process PDF
- [BUG] Java LSP (JDTLS) Hover Operation Hangs on Complex Classes
- Incorrect low funds warning on all responses when launched from Windows Explorer -> WSL (API usage plan)
- [BUG] Persistent API Connection errors preventing all work [10/27/25] THREE DAYS NOW!!!
- [Bug] Anthropic API Error: Server Overloaded (500)
- 5-hour limit reached ∙ resets 12pm
- [Bug] Anthropic API: Opus Model Functionality Discrepancy Between CLI and Web Interface
- Invalid JSON Parsing: Malformed Unicode Surrogate in Request Body
- Persistent Anthropic API Connection Failures During Build Process
- [Bug] Anthropic API Error: Persistent 429 Rate Limit Responses Consuming Credits
- [BUG] Claude Code Terminal - API Error: Rate limit reached despite low usage (Pro account)
- /remote-control fails with 400 'Failed to convert session context' when system prompt is large
- [BUG] Cowork API connection issue + Coworke Tab disappears on restart
- Persistent "API Error: Connection error" and Request Timed Out in WSL2 Environment
- [BUG] API Error: 400 due to tool use concurrency issues.
- [BUG] getting frequent error as - API Error: 400 due to tool use concurrency issues.
- API Error 500 - Internal server error on simple text message
- Claude Agent SDK: 80+ second startup time on Windows
- [Bug] Anthropic API Error: Invalid thinking parameter in requests
- [Bug] Anthropic API Error: 413 Request Entity Too Large causing infinite loop
- [BUG] api error when i upload a picture from a chatbot
- Anthropic API Billing: Persistent Model Access Restriction
- [BUG] "message":"messages.2: `tool_use` ids were found without
- [Bug] Opus Model Access Blocked Despite MAX 20x Plan Subscription
- Anthropic API Request Timeout During Long-Running Code Generation Task
- Persistent Network Fetch Failure with Exponential Backoff Retry
- Persistent Anthropic API Connection Failures with Exponential Backoff Retry
- Invalid JSON Request: Malformed Surrogate Character in API Payload
- Claude AI usage limit reached|1753560000
- [BUG] EDITED: Claude Code fails on mobile networks due to IP-based connections instead of hostname-based HTTPS
- [BUG] Unable to connect Anthropic services
- Windows WSL2 consistent API Errors
- VS Code Claude extension API usage limit reached
- [BUG]
- [BUG] Persistent API Error: 400 for 12+ hours across multiple networks and locations
- [Bug] Rate Limiting Error Despite Normal Web App Usage Metrics
- [BUG] Visual Studio Code: API Error: 400 due to tool use concurrency issues.
- [Bug] Anthropic API Error: Cannot modify thinking blocks in assistant messages
- Multiple concurrent CLI instances corrupt thinking blocks even from different directories
- [BUG] Conversation breaks(throws 400) after image encoding error
- [Bug] Rate Limits Severely Reduced for 5x Subscription Plan
- [BUG] Claude Code VS Code extension throws an error when re-reading an image that was previously read successfully, and the chat cannot continue afterward
- [Bug] Anthropic API: Extended Thinking timeout without user feedback causing CLI hang
- [BUG] alse positive content filter on standard React form component
- API Error 500: Internal Server Error when sending any message in Claude Code (Cursor, Windows)
- [Bug] Unable to access Claude Sonnet model via /model command
- [Bug] Anthropic API Error: Internal server error with Claude 4.5 Sonnet
- [BUG] After a compact, if I ask Claude code to read a file pdf, md or csv, I receive an API 400.
- [Bug] Anthropic API Error: Missing Tool Result Block
- [BUG] Authentication Loop: API Key Ignored, OAuth Repeatedly Fails, Making Claude Code Unusable
- [BUG] Process Hangs Indefinitely When Reading InputStream from Claude Code Headless Execution
- [Bug] Anthropic API Error: Intermittent AUP Violation Detection During Project Tasks
- Missing Tool Result Block for Tool Use ID toolu_013UyW5GhFet72wyp1nt5NrC
- Missing Tool Result Block for Tool Use ID
- Invalid JSON Request: Malformed Surrogate Character in API Payload
- Unresolvable TypeError: fetch failed on Clean WSL Installation
- [BUG] API Error: 400 reasoning `encrypted_content` was not issued to this caller
- [BUG] This is frustating to get usage limit issue because of Anthropic capacity limitation
- Bug: Opus 4.7 (1M context) rejects requests with role 'system' is not supported on this model
- API Error 500 - Internal server error occurring repeatedly