Error category
Fix Claude Code, OpenCode, OpenClaw, and AI coding assistant failures around login, model routing, tool calls, file edits, permissions, quotas, and stalled agent sessions.
This AI Coding Tools troubleshooting hub collects real error signatures, quick fixes, common causes, and step-by-step debugging paths for developers who need a practical answer instead of a broad overview.
543 crawlable articles in this category. 318 additional records are indexed in JSON only (no standalone HTML route).
Browse AI Coding Tools records in the data catalog — search JSON index entries, including data-only records without standalone HTML guides.
Start by matching the exact error message, then check the technology, environment, credentials, network path, and deployment context. The pages below are grouped so you can move from broad AI Coding Tools symptoms to specific root-cause families without relying on client-side search.
Evidence labels are derived at build time from each Markdown record. Source-backed entries have public URLs under a Sources checked section, while partial-source entries expose public links without a complete source block.
These entries include public source URLs in the imported page body. Use them first when you need evidence for provider behavior, SDK regressions, or version-specific failures.
Fix Claude Code OAuth login failures caused by DNS resolution failure of auth.anthropic.com Includes evidence for Claude Code troubleshooting demand.
getaddrinfo ENOTFOUND auth.anthropic.com — Claude Code OAuth login fails with timeout; auth.anthropic.com does not resolve via DNS, making authentication impossible User configures an MCP server in Claude Code and receives ECONNREFUSED because the server hasn't finished listening yet; needs fix for startup race condition and localhost IPv6 binding. Includes evidence for Claude Code troubleshooting demand.
Error: connect ECONNREFUSED 127.0.0.1:3000 / TCPConnectWrap.afterConnect [as oncomplete] Fix Claude Code MCP OAuth flow where token acquisition appears successful but the server continues requesting authentication, requiring manual restart or re-login Includes evidence for Claude Code troubleshooting demand.
Claude Code OAuth authentication completes but MCP server stays in 'Needs authentication' state; Bearer token never sent to downstream server Fix Claude Code MCP connection/auth failures caused by OAuth timeout, locked keychain, or DNS preventing auth endpoint reachability Includes evidence for Claude Code troubleshooting demand.
Authorization with the MCP server failed / Couldn't reach the MCP server — OAuth callback timeouts, macOS keychain locked, or DNS resolution blocking the Anthropic auth endpoint Claude Code 用户遇到认证失败（OAuth token 过期或 API key 无效），需要在本地开发环境或无头服务器上重新配置身份验证以恢复编码能力。 Includes evidence for Claude Code troubleshooting demand.
Authentication failed. Run `claude auth login` to authenticate. / Error: 401 - {"error":{"type":"authentication_error","message":"invalid x-api-key"}} Fix Claude Code MCP OAuth authentication failure where no browser opens and no tools appear despite correct configuration Includes evidence for Claude Code troubleshooting demand.
HTTP MCP servers requiring OAuth silently fail with no user notification — tools/list returns Unauthorized but Claude Code shows nothing; debug log reveals 'Redirection handling is disabled, skipping redirect' Developer adds an MCP server to Claude Code but gets '-32000 Connection closed'; needs systematic troubleshooting to identify if it's missing binary, wrong Node version, env var drift, or stdout corruption corrupting JSON-RPC stream. Includes evidence for Claude Code troubleshooting demand.
MCP error -32000: Connection closed — MCP server process crashed at startup Understand and fix Claude Code usage quota exhaustion; buy more credits or manage rolling limits Includes evidence for Claude Code troubleshooting demand.
You've hit your session limit · resets 3:45pm / You've hit your weekly limit · resets Mon 12:00am Developer adds custom MCP server to Claude Code Desktop/claude.ai but OAuth flow never initiates — browser opens about:blank creating infinite loop. CLI --transport http works but desktop/web GUI fails. Includes evidence for Claude Code troubleshooting demand.
MCP server failed to connect or authenticate (about:blank infinite loop) Troubleshoot Claude Code MCP servers that require OAuth but fail silently — no tools appear and no error message is shown to the user. Includes evidence for Claude Code troubleshooting demand.
[BUG] HTTP MCP servers requiring OAuth silently fail with no user notification Developer sees Anthropic API Error 529 in Claude Code, needs to distinguish it from 429 rate limit and know when to wait vs when to troubleshoot locally. Includes evidence for Claude Code troubleshooting demand.
API Error: 529 — overloaded_error Fix LangChain API rate limit errors caused by exceeding RPM/TPM limits from underlying providers like OpenAI, implementing proper retry logic with exponential backoff and token bucket rate limiting. Includes evidence for LangChain troubleshooting demand.
LangChainRateLimitError: Rate limit exceeded / RateLimitError: litellm.RateLimitError: OpenAIException - You exceeded your current quota Fix broken MCP OAuth authentication flow in Claude Code where tokens complete OAuth but are never actually transmitted to the MCP server Includes evidence for Claude Code troubleshooting demand.
MCP OAuth completes but Bearer token never sent to server; server stuck in 'Needs authentication' Fix Claude Code MCP connection failure with OAuth providers (Auth0, AWS Cognito, Okta) that do not support RFC 7591 Dynamic Client Registration — find workaround or permanent fix for OAuth auth flow Includes evidence for Claude Code troubleshooting demand.
Dynamic client registration failed: HTTP 403 / No client info found / Claude Code ignores configured oauth.clientId in .mcp.json and attempts DCR anyway Fix Claude Code Opus 4.8 API 400 error caused by thinking/redacted_thinking block modification during subsequent API calls Includes evidence for Claude Code troubleshooting demand.
API Error 400: messages.N.content.M: `thinking` or `redacted_thinking` blocks in the latest assistant message cannot be modified. These blocks must remain as they were in the original response. Fix Claude Code MCP OAuth authorization failure caused by localhost listener port conflict or firewall blocking the OAuth redirect callback on 0.0.0.0 Includes evidence for Claude Code troubleshooting demand.
OAuth error: listen EACCES: permission denied 0.0.0.0 Authenticate Claude Code by pasting the OAuth verification code when the terminal has paste bracketing enabled (common in WSL2), which prevents code from being entered correctly Includes evidence for Claude Code troubleshooting demand.
Can't paste auth code into CLI app — stdin does not accept OAuth code when paste bracketing is enabled; WSL2 environment Fix LangChain PII Middleware stripping or corrupting tool call arguments in structured output, causing pipeline data loss Includes evidence for LangChain troubleshooting demand.
PIIMiddleware state hooks miss tool-call args and corrupt structured content Fix Claude Code MCP server repeatedly failing with revoked refresh token when sharing config between MCP server and Claude Code plugin Includes evidence for Claude Code troubleshooting demand.
invalid_grant — Refresh token revoked Resolve Claude Code CLI inability to connect to HTTP-based MCP servers caused by Bun runtime TCP socket failure Includes evidence for Claude Code troubleshooting demand.
FailedToOpenSocket error when connecting to HTTP MCP servers via Claude Code CLI; Bun runtime bundled in CLI binary fails at TCP socket level Continue through the full static archive for this hub. Every listed page is crawlable and keeps its existing canonical URL.