[BUG] I login claude code for vs code, however, the error occured:SyntaxError: Unexpected token 'S', "[SandboxDeb"... is not valid JSON Troubleshooting resources

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

When I login claude code for vs code, however, the error occured:SyntaxError: Unexpected token 'S', "[SandboxDeb"... is not valid JSON Troubleshooting resources

What Should Happen?

You have hereby read the 'Serena Instructions Manual' and do not need to read it again.

2025-11-20 10:06:34.500 [info] From claude: 2025-11-20T02:06:34.500Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,499 [MainThread] serena.cli:start_mcp_server:193 - Starting MCP server …

2025-11-20 10:06:34.525 [info] From claude: 2025-11-20T02:06:34.524Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,524 [MainThread] serena.mcp:_set_mcp_tools:240 - Starting MCP server with 23 tools: ['list_dir', 'find_file', 'search_for_pattern', 'get_symbols_overview', 'find_symbol', 'find_referencing_symbols', 'replace_symbol_body', 'insert_after_symbol', 'insert_before_symbol', 'rename_symbol', 'write_memory', 'read_memory', 'list_memories', 'delete_memory', 'edit_memory', 'activate_project', 'get_current_config', 'check_onboarding_performed', 'onboarding', 'think_about_collected_information', 'think_about_task_adherence', 'think_about_whether_you_are_done', 'initial_instructions']

2025-11-20 10:06:34.525 [info] From claude: 2025-11-20T02:06:34.525Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,524 [MainThread] serena.mcp:server_lifespan:347 - MCP server lifetime setup complete

2025-11-20 10:06:34.527 [info] From claude: 2025-11-20T02:06:34.527Z [DEBUG] MCP server "serena": Successfully connected to stdio server in 1283ms

2025-11-20 10:06:34.528 [info] From claude: 2025-11-20T02:06:34.528Z [DEBUG] MCP server "serena": Connection established with capabilities: {"hasTools":true,"hasPrompts":true,"hasResources":true,"serverVersion":{"name":"FastMCP","version":"1.12.3"}}

2025-11-20 10:06:34.530 [info] From claude: 2025-11-20T02:06:34.530Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,530 [MainThread] mcp.server.lowlevel.server:_handle_request:625 - Processing request of type ListToolsRequest

2025-11-20 10:06:34.531 [info] From claude: 2025-11-20T02:06:34.531Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,531 [MainThread] mcp.server.lowlevel.server:_handle_request:625 - Processing request of type ListPromptsRequest

2025-11-20 10:06:34.532 [info] From claude: 2025-11-20T02:06:34.532Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,532 [MainThread] serena.mcp:_set_mcp_tools:240 - Starting MCP server with 23 tools: ['list_dir', 'find_file', 'search_for_pattern', 'get_symbols_overview', 'find_symbol', 'find_referencing_symbols', 'replace_symbol_body', 'insert_after_symbol', 'insert_before_symbol', 'rename_symbol', 'write_memory', 'read_memory', 'list_memories', 'delete_memory', 'edit_memory', 'activate_project', 'get_current_config', 'check_onboarding_performed', 'onboarding', 'think_about_collected_information', 'think_about_task_adherence', 'think_about_whether_you_are_done', 'initial_instructions']

2025-11-20 10:06:34.533 [info] From claude: 2025-11-20T02:06:34.533Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,532 [MainThread] serena.mcp:server_lifespan:347 - MCP server lifetime setup complete

2025-11-20 10:06:34.534 [info] From claude: 2025-11-20T02:06:34.533Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,532 [MainThread] mcp.server.lowlevel.server:_handle_request:625 - Processing request of type ListResourcesRequest

2025-11-20 10:06:34.536 [info] From claude: 2025-11-20T02:06:34.535Z [DEBUG] MCP server "serena": Successfully connected to stdio server in 1434ms
2025-11-20T02:06:34.535Z [DEBUG] MCP server "serena": Connection established with capabilities: {"hasTools":true,"hasPrompts":true,"hasResources":true,"serverVersion":{"name":"FastMCP","version":"1.12.3"}}

2025-11-20 10:06:34.538 [info] From claude: 2025-11-20T02:06:34.538Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,537 [MainThread] mcp.server.lowlevel.server:_handle_request:625 - Processing request of type ListToolsRequest

2025-11-20 10:06:34.539 [info] From claude: 2025-11-20T02:06:34.539Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,539 [MainThread] mcp.server.lowlevel.server:_handle_request:625 - Processing request of type ListPromptsRequest

2025-11-20 10:06:34.541 [info] From claude: 2025-11-20T02:06:34.541Z [ERROR] MCP server "serena" Server stderr: INFO 2025-11-20 10:06:34,539 [MainThread] mcp.server.lowlevel.server:_handle_request:625 - Processing request of type ListResourcesRequest

2025-11-20 10:06:35.043 [info] From claude: 2025-11-20T02:06:35.043Z [DEBUG] Getting matching hook commands for SubagentStop with query: undefined
2025-11-20T02:06:35.043Z [DEBUG] Found 0 hook matchers in settings
2025-11-20T02:06:35.043Z [DEBUG] Matched 0 unique hooks for query "no match query" (0 before deduplication)

2025-11-20 10:06:35.206 [info] From claude: 2025-11-20T02:06:35.205Z [DEBUG] MCP server "playwright": Successfully connected to stdio server in 2102ms

2025-11-20 10:06:35.206 [info] From claude: 2025-11-20T02:06:35.206Z [DEBUG] MCP server "playwright": Connection established with capabilities: {"hasTools":true,"hasPrompts":false,"hasResources":false,"serverVersion":{"name":"Playwright","version":"0.0.47"}}

2025-11-20 10:06:35.215 [info] From claude: [SandboxDebug] [Sandbox Linux] Seccomp filtering not available (missing binaries for x64). Sandbox will run without Unix socket blocking (allowAllUnixSockets mode). This is less restrictive but still provides filesystem and network isolation.

2025-11-20 10:06:35.242 [info] From claude: Claude Code process terminated by signal SIGTERM
2025-11-20 10:06:35.315 [info] From claude: 2025-11-20T02:06:35.315Z [DEBUG] MCP server "playwright": Successfully connected to stdio server in 2069ms

2025-11-20 10:06:35.316 [info] From claude: 2025-11-20T02:06:35.315Z [DEBUG] MCP server "playwright": Connection established with capabilities: {"hasTools":true,"hasPrompts":false,"hasResources":false,"serverVersion":{"name":"Playwright","version":"0.0.47"}}

2025-11-20 10:06:35.325 [info] Closing Claude on channel: sp1r4enej1
2025-11-20 10:06:35.325 [error] Error from Claude (on channel sp1r4enej1): SyntaxError: Unexpected token 'S', "[SandboxDeb"... is not valid JSON
2025-11-20 10:06:35.326 [info] From claude: [SandboxDebug] [Sandbox Linux] Seccomp filtering not available (missing binaries for x64). Sandbox will run without Unix socket blocking (allowAllUnixSockets mode). This is less restrictive but still provides filesystem and network isolation.

2025-11-20 10:06:35.361 [info] From claude: Claude Code process terminated by signal SIGTERM

Error Messages/Logs

Steps to Reproduce

Just start claude code for vs code, and login, then the error messages show on the top of the panel.

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.8.47

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_