MCP server connection issues — page 2
Issues 201–400 of the 9,294 matching this topic. The trend chart and topic overview are on page 1.
- [BUG] Cowork — GitHub connector unusable: OAuth DCR unsupported, UI shows misleading state, Disconnect button dead
- Scheduled tasks cannot access HTTP MCP servers — missing user:mcp_servers scope
- [Bug] Context limit reached with 32k tokens free space and auto-compact disabled
- context_window.used_percentage doesn't match internal context warning calculation
- [Bug] Claude in Chrome Native Host crashes on Windows 11 - Bun internal assertion failure
- [BUG] MCP roots capability advertised but roots/list method not implemented
- Terminal renderer CPU spin: 100% CPU with 625K writes/0 blits on large session
- [BUG] Can't Authenticate With Notion MCP
- Context low warning and /compact failure despite having 86% free context space
- [BUG] Claude Desktop Drops/Reverts Long Multi-Step Tasks Without Warning
- [Bug] Subagents unable to write files and call MCP tools silently
- Dynamic MCP resources not discovered in claude code
- [BUG] Claude Code fails to expose MCP tools to AI sessions when running a local Playwright MCP server
- [BUG] Task tools (TaskCreate/TaskGet/TaskList/TaskUpdate) silently disabled on Opus 4.8 / Sonnet 5 / Fable 5 by model-id gate `tengu_vellum_ash` — no error, no override, ToolSearch reports them as nonexistent
- [FEATURE] Support `envFile` in `.mcp.json` for loading secrets before env var expansion
- Compaction fails with 'Conversation too long' at 48% context usage (Opus 4.6)
- [BUG] Claude Code Configuration File Corruption
- [Bug] Fable 5 safeguard `[reasoning_extraction]` false-positives on a one-word greeting ("Hi")
- [BUG] MCP Agent tool reports an empty available-agent list in mcp serve mode
- [Bug] GitHub connector missing from MCP list despite showing in settings
- MCP OAuth token refresh not persisting for Notion MCP server
- Claude Desktop: Built-in MCP servers 'Claude in Chrome' and 'mcp-registry' fail to connect (Failed to get account UUID)
- Feature: Expose session ID as $CLAUDE_SESSION_ID environment variable
- MCP Configuration Inconsistency: CLI-managed vs File-based configs
- Cluade Code in Windows is a pain in ***
- [FEATURE] Be Able to Add a OAuth-Compliant Credential Manager for Claude Connectors
- [Feature] Reconnect/restart MCP servers from Claude Code in Claude Desktop without Cmd+Q (expose /mcp UI or auto-reconnect)
- Explore agent always fails with "Prompt is too long" when many MCP tools are connected
- MCP OAuth fails with providers requiring HTTPS redirect URIs
- API Error: 400 with "messages.31.content.4.image.source.base64.data: Image does not match the provided media type image/jpeg"
- Bug: Task tool fails with "tools: Tool names must be unique" error
- [BUG] `ide:getDiagnostics` times out if file is not active in Jetbrains IDE
- Linear MCP OAuth fails with "Invalid client" — metadata-URL clientId + ephemeral loopback port
- [BUG] GitHub MCP authenticate tool redirects OAuth flow to Google Drive consent screen instead of GitHub
- Sub-agents spawned via Agent tool don't reliably inherit MCP tools (inconsistent with docs)
- [FEATURE] Expose pasted image data to hooks and plugins
- [Feature Request] Include actual context window usage in statusline JSON
- [BUG] Authentication fails immediately after successful /login in Claude Code v1.0.71
- [Feature Request] Add LaTeX/KaTeX math rendering to TUI
- Unhandled case: [object Object] on stream end with had_error: true after long sessions
- [Bug] v2.1.117 regression: parallel Bash tool calls corrupt fd 3 in nested-Docker sandbox; permanent /proc/self/fd/3: Permission denied
- Expose organization API credit balance to statusLine scripts (and via Admin API)
- --dangerously-load-development-channels should support skipping the confirmation dialog
- HTTP 529 Overloaded errors occurring frequently on Max plan with Claude Opus 4.6
- Claude in Chrome extension not connecting on Windows despite MCP server showing "connected"
- [BUG] Claude Desktop Local mode rejects folders outside C:\Users on Windows, even with valid MCP config
- [BUG] MCP OAuth Integration Fails on Production Deployments with step=start_error
- [BUG] Claude CLI: URL-mode elicitation/create not supported — server-initiated OAuth flows fails with not supported error
- [BUG] Cowork /schedule skill fails — create_scheduled_task tool not injected into session context (Windows)
- [FEATURE] PermissionRequest and PermissionResponse hook events for metrics
- [BUG] Background subagents cannot access MCP tools
- Task tool fails with 'Tool names must be unique' error when MCP servers are enabled
- [BUG] Claude Code CLI Isn't Detecting Project Scoped MCP Server
- Support Streamable HTTP MCP Servers (e.g. Smithery)
- Routines in Claude Code can't use Claude.ai Connectors (e.g., Composio, Gmail, LinkedIn)
- Cowork sessions fail with 'Connection error' - internal MITM proxy blocking api.anthropic.com
- [BUG] GitLab MCP plugin fails to reconnect - "Failed to reconnect to plugin:gitlab:gitlab"
- Claude in Chrome: Native messaging host not installed for Chromium/Brave browsers (Linux)
- [Bug] Anthropic API Error: PNG screenshots sent with incorrect image/jpeg MIME type
- VS Code webview shows `Unhandled case: [object Object]` and stops rendering while CLI backend keeps running
- [FEATURE] API / sync mechanism for Claude Team Project knowledge files
- Chrome extension: MCP server never connects to native host socket
- claude_design MCP fails: 404 from api.anthropic.com/v1/design/mcp (harness-injected, unremovable)
- [FEATURE] Multi-agent collaboration across machines (Agent-to-Agent protocol)
- [BUG] COWORK || Local / desktop MCP tools not exposed to claude cowork, all the tools work properly in claude chat
- Custom Subagents Cannot Access Project-Scoped MCP Servers (Hallucinate Instead)
- Feature Request: Improve Claude Code Token Management with MCP Servers
- Unify MCP configuration and separate from conversation history
- Claude-in-Chrome Windows & WSL working fixes
- Feature Request: MCP to access Claude.ai chat history and Projects
- Feature Request: Agent-Scoped MCP Servers to Prevent Context Window Overflow
- Claude Code doesn't respond to MCP notifications/prompts/list_changed for dynamic command updates
- [FEATURE] `--permission-prompt-tool ` needs minimal, working example and documentation for MCP integration with Claude Code CLI
- [Bug] Sharp increase in token consumption since April 5-6 weekend — Max plan 5h limits hit in ~1-2h
- [BUG] Can't specify OAuth scope for Snowflake MCP
- MCP channel notifications (notifications/claude/channel) not surfaced to conversation
- [BUG] claude.ai MCP integrations (Gmail, Google Calendar) not available in -p mode or --resume sessions since v2.1.79
- [BUG] GitHub Issue: Bash tool EINVAL on Windows
- [Bug] MCP authentication prompt hangs when pressing enter to continue
- [BUG] Claude Code sustained ~80% ECONNRESET failure rate — March 30, 2026 specifically from Boston Area
- [BUG] MCP resources not available for subagents
- [BUG] Claude Opus 4 limit reached, now using Sonnet 4
- [BUG] Claude Code 2.1.243 immediately segfaults on Arch Linux x86_64
- CRITICAL: claude.ai MCP connector OAuth completes but Bearer token never sent to server
- [BUG] MCP deferred tools not available on first turn — breaks scheduled/automated tasks
- Cowork sessions don't inject user_config env vars into MCP server processes
- [BUG] Official marketplace fails to load due to unsupported "git-subdir" source type in semgrep plugin
- [Bug] /compact fails with "Tool names must be unique" even after disabling all MCP servers (v2.0.70)
- Feature Request: Add support for MCP Elicitation
- [BUG] Claude Desktop: external stdio MCP tools announced but never dispatched in Chat mode (zero tools/call) — Windows/macOS/Linux, all install types
- [BUG] macOS 26.5.1 kernel zone leak (data.kalloc.1024) from Claude Code CLI — claude.exe panics at ~20GB, leak rate scales 21→1027/sec with agent load
- [BUG] Claude for PowerPoint: MCP connector tools are not loaded into Claude's tool list at session start; only become available after refresh_mcp_connectors runs
- [BUG] Claude in Chrome + Control Chrome Failures in Cowork Mode
- Claude Code hangs indefinitely on startup in non-git directories (regression since 2.1.31)
- [BUG] Repeated API 500 "Internal server error" during single Claude Code session (3 occurrences)
- [FEATURE] Rewrite Claude Code Client in the V Programming Language
- [BUG]
- Feature Request: CLI command to list available MCP tools and servers
- 2.1.178: native team-management tools TeamCreate / TeamDelete no longer surfaced (regression from 2.1.177)
- Allow opt-out of built-in deferred tools via settings to reduce baseline context
- [BUG] Atlassian MCP Server Tools Not Available in Claude Code 2.0.10 Conversations Despite Successful Connection
- Assistant text emitted before a tool call in the same turn (esp. AskUserQuestion) is intermittently never rendered to the user
- [FEATURE] Make Workflow scripts (.claude/workflows/*.js) a distributable plugin component
- [BUG] Cowork: "Reached maximum number of turns (100)" breaks long-running browser automation projects
- [BUG] MCP OAuth with multiple terminals open causes re-auth
- [BUG] Slack MCP "Failed to connect" — cannot reconnect after re-authentication
- [FEATURE] WhatsApp channel support (alongside Telegram/Discord)
- [BUG] Claude Desktop "Something went wrong loading this session" - React #185 infinite loop on specific project directory
- [BUG] Desktop Extension MCP servers not passed to Cowork VM despite being enabled in session config
- Project-scoped plugins: install command fails for new projects, Discovery tab incorrectly hides plugin
- [BUG] v1.0.98 is not reading project .mcp.json and rewriting .claude/settings.local.json
- [BUG] MCP Timeout needs to be configurable
- Support selective enable/disable of individual claude.ai MCP servers
- [FEATURE] Native OTLP Trace/Span Export for Claude Code
- [BUG] Claude Desktop MCP tool calls hang until user clicks/expands panel
- [BUG] MCP tools running sequentially instead of in parallel in v2.0.71
- [BUG] MCP servers requiring OAuth authentication don't expose tools - no browser auth flow triggered
- [Bug] Native build 2.1.243 segfaults on glibc 2.44 due to malloc/free symbol interposition
- [BUG] MCP tool calls in CCR Routines fail with "requires approval" — no approval UI shown, reconnect does not resolve
- Channel notifications dropped during hook execution
- Claude Max + Claude Code rate limits exhausting abnormally fast / possible metering bug
- Telegram channel stops processing inbound messages after completing a turn
- [BUG] M365 MCP OAuth fails with AADSTS9000411 - parameter 'prompt' is duplicated
- [BUG] v2.1.68 (updated 2026-03-04) opens 3 blank VS Code windows when claude is started in the integrated terminal.
- [BUG] Slash commands not working - "Unknown skill" error for all built-in commands
- [BUG] MCP tool parameters with $ref schemas are incorrectly serialized as strings
- Claude Desktop Cowork tab fails to connect - ERR_CONNECTION_RESET at auth step
- [Bug] VS Code Extension: Failed Connection to Linear MCP Service
- Feature Request: Add wildcard support for MCP tool permissions
- Project scope MCP servers not displayed in claude mcp list command
- [Desktop] iOS Simulator panel: claude-ios-sim crash-loops in Metal/CoreImage on macOS 27.0 beta — panel stuck on 'Attach a simulator'
- [BUG] Tool-call results empty in live UI then flush late/out-of-order (Bash, Read, MCP, advisor) — macOS, Opus 4.8, parallel batches
- [BUG] Claude Code web session loses GitHub push access mid-project
- [BUG] Claude Code Web interactive sessions lost all claude.ai MCP connectors ~April 23, 2026 while routines retain them
- [BUG] Glob and Grep tools missing from tool palette in 2.1.117 (regression)
- mcp__Claude_in_Chrome__navigate silently denies non-pre-approved domains — no user-facing approval path exists anywhere
- 93% rate limit consumed in ~3 minutes on fresh session (Max plan, v2.1.85)
- [BUG] Telegram plugin inbound messages not delivered to Claude Code session (notifications/claude/channel not surfaced)
- [FEATURE] CLI-as-remote-control-client — connect to a remote session from another terminal
- [BUG] deniedMcpServers serverName regex rejects plugin MCP server names
- [BUG] MCP OAuth redirect_uri hardcodes the `localhost` hostname — breaks IdPs that allowlist only `127.0.0.1`
- Assistant text between tool calls is not rendered, not shown in ctrl-o, and not saved to the session file
- [Bug] Stray token "count" injected before tool calls causes parse failure in Claude Code
- [BUG] Plugin skills not appearing in `/` menu after v2.1.110 update — only `schedule` shows
- [FEATURE] Prefer plain text over image when pasting from rich text sources (e.g. Word, Excel)
- MCP stdio servers never auto-reconnect after disconnect
- [BUG] Claude Code spawns duplicate channel plugin instances mid-session, causing 409 Conflict and tool loss
- [BUG] OpenTelemetry logs MCP tools as generic 'mcp_tool' instead of specific tool names like 'mcp__context7__resolve-library-id'
- Having multiple MCP servers running Eats into Context Window
- use MCPClient resetTimeoutOnProgress=True to support long MCP tool calls
- Opus model quality regression — significant degradation starting ~April 15, 2026
- Opus 4.6 (Max $100) — Quota reaches 93% after minimal prompting in a single session
- Claude in Chrome Extension Not Connecting on Windows 11
- Chrome Extension: EADDRINUSE - Native Host and MCP Server both try to create pipe listener
- Feature Request: Programmatic API for enabling/disabling MCPs without restart
- Feature Request: Zero-Trust Architecture for Environment Variable Security
- [BUG]
- Hard block on typing passwords breaks legitimate dev/test workflows - needs a permission-gated opt-in for own dev environments
- [Bug] Weekly usage limit reset occurring before scheduled reset time & new week ends in 5 days, not 7 days
- Custom agents cannot use deferred MCP tools even when declared in mcpServers/tools frontmatter
- Claude in Chrome: 'Browser extension is not connected' despite correct setup (v2.1.39 + ext v1.0.47)
- Bug: HTTP MCP client ignores no_proxy environment variable
- Windows 11: Terminal freezes on startup in 2.1.30/2.1.31 (regression from 2.1.29)
- [Bug] Claude in Chrome fails when Claude Desktop native messaging host config exists (macOS)
- TypeScript LSP plugin enabled but tools not available in session
- [FEATURE] Remote Development Support for Chrome Extension
- [BUG] Local MCP server will not trust self-signed certs
- [BUG] `claude mcp add` command fails when options are placed before required arguments
- Tool Result Block Missing in Async Promise Handling
- [BUG] MCP Server Integration: protocolVersion validation error with stdio servers
- [BUG] Remote Routine — MCP connector calls blocked by 'approval required' despite Always Allow (Team plan, macOS)
- [BUG] 2.1.111 introduced ~14% context window bloat at session startup (8% → 22%)
- [Bug] Anthropic API Error: Internal Server Error (500)
- [BUG] MCP tools not available on first turn in Remote Trigger / Scheduled sessions
- [BUG] [regression] HTTP MCP server with Bearer token shows "needs-auth" in claude -p mode since 2.1.83 (worked in 2.1.81)
- MCP OAuth tokens not auto-refreshing despite valid refresh tokens
- [FEATURE] Setting to suppress built-in token/usage warning notifications in statusline
- Memory leak causing V8 OOM crashes (SIGABRT) on extended sessions
- [FEATURE] VSCode Extension: Add SSE transport support for MCP servers (already supported in CLI)
- [BUG] Tool usage output no longer shows executed command in versions > 1.0.123
- [BUG] HTTP/SSE MCP Transport Ignores Authentication Headers
- [ENHANCEMENT] MCP Resources Pagination Support for ListMcpResourcesTool
- [BUG] Claude Code MCP tool calls fail with 'String should have at most 64 characters' error due to internal prefix addition.
- [BUG] High usage while using Opus 4.6
- [Bug] Ink renderer crashes in spawned teammate agents during tmux mode sessions
- MCP OAuth tokens expire frequently, requiring manual /mcp reconnect
- Figma MCP: generate_figma_design tool not available in Claude Code
- [Feature Request] Allow posting images (screenshots) to GitHub PR/Issue comments
- Xcode MCP tools requiring Automation permission hang indefinitely for CLI clients without bundle identifiers
- [BUG] IDE integration broken in v2.1.23+ - MCP server never connects - Affects Jetbrains IDEs on Windows
- [BUG] ExitPlanMode tool fails with "AbortError" - hangs indefinitely when MCP servers active
- Feature Request: disabled option for MCP servers in .mcp.json
- [BUG] MCP servers connect successfully but tools are not exposed to assistant
- Link to JSON Schema for settings.json in the official docs
- Subagent launch fails with 'Tool names must be unique' when MCP server is configured
- Add MCP Registry support for centralized enterprise management of MCP servers
- Feature Request: Enhance Hooks with Integrated Types (MCP Tool, Inline Script, API Call)
- .mcp.json file is not being loaded
- [BUG] Cross-session send_message reports success but message is never delivered (stuck loading, 0/4 delivery)
- [BUG] macOS: filesystem-class MCP tool calls silently dropped between approval gate and local server dispatch — survives app rollback, extension reinstall, new connector identity (started 2026-07-21→22 with no local change)