fix: Claude Desktop MCP JSON parsing errors after July 23, 2025 breaking change#4
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WSHAPER wants to merge 1 commit intofkesheh:mainfrom
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fix: Claude Desktop MCP JSON parsing errors after July 23, 2025 breaking change#4WSHAPER wants to merge 1 commit intofkesheh:mainfrom
WSHAPER wants to merge 1 commit intofkesheh:mainfrom
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…ing change - Add wrapper.ts to redirect console output away from JSON-RPC channel - Comment out console.error/log statements in index.ts and start.ts - Implement factory pattern for clean, DRY logging architecture CONTEXT: On July 23, 2025, Anthropic deployed infrastructure changes (ASN 399358) that enforced strict JSON-RPC parsing in Claude Desktop. Console output mixing with JSON-RPC now causes parsing failures: "Unexpected token 'S', 'Starting C'... is not valid JSON" SOLUTION: Console output wrapper redirects all debug logs to /tmp/mcp-code-context.log while preserving pure JSON-RPC communication on stdout/stdin. Resolves: Complete MCP functionality breakdown Affected: All MCP servers with console.log/error statements Timeline: Issue began July 23, 2025 (GitHub issues [#4188](anthropics/claude-code#4188), [#4228](anthropics/claude-code#4228)) The wrapper approach restores pre-July 23 compatibility while maintaining full debug capabilities for troubleshooting.
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CONTEXT: On July 23, 2025, Anthropic deployed infrastructure changes (ASN 399358) that enforced strict JSON-RPC parsing in Claude Desktop. Console output mixing with JSON-RPC now causes parsing failures: "Unexpected token 'S', 'Starting C'... is not valid JSON"
SOLUTION: Console output wrapper redirects all debug logs to /tmp/mcp-code-context.log while preserving pure JSON-RPC communication on stdout/stdin.
Resolves: Complete MCP functionality breakdown
Affected: All MCP servers with console.log/error statements
Timeline: Issue began July 23, 2025 (GitHub issues #4188, #4228)
The wrapper approach restores pre-July 23 compatibility while maintaining full debug capabilities for troubleshooting.