Fix JSON-RPC 2.0 notification handling in StreamableHttpServerWrapper#28
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Fix JSON-RPC 2.0 notification handling in StreamableHttpServerWrapper#28
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According to JSON-RPC 2.0 specification section 4.1: "A Notification is a Request object without an 'id' member... The Server MUST NOT reply to a Notification." Previously, the StreamableHttpServerWrapper would pass notifications to the handler and return whatever response it produced (typically an error for unknown methods like 'notifications/initialized'). This caused MCP clients like OpenAI Codex CLI to fail during handshaking. This fix: - Detects notifications by checking for missing/null 'id' field - Returns 202 Accepted with no response body for notifications - Still calls the handler so notification processing can occur - Silently ignores any handler errors for notifications Added test_notification_handling() to verify: - notifications/initialized returns 202 with empty body - notifications/cancelled returns 202 with empty body Fixes compatibility with MCP clients that follow the JSON-RPC 2.0 spec.
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Adds .githooks/pre-commit that automatically formats staged C++ files before commit. This prevents formatting issues from reaching CI. To enable: git config core.hooksPath .githooks The hook: - Finds clang-format (prefers versioned like clang-format-19) - Formats only staged .cpp/.hpp/.h/.c files - Re-stages formatted files automatically
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Summary
This PR fixes JSON-RPC 2.0 notification handling in
StreamableHttpServerWrapperand adds a pre-commit hook for automatic formatting.1. Fix: JSON-RPC 2.0 Notification Handling
According to JSON-RPC 2.0 specification section 4.1:
Previously,
StreamableHttpServerWrapperwould pass notifications to the handler and return whatever response it produced. For unknown notification methods likenotifications/initialized, this resulted in error responses like:{"error":{"code":-32601,"message":"Method 'notifications/initialized' not found"},"id":null,"jsonrpc":"2.0"}This caused MCP clients (like OpenAI Codex CLI) to fail during handshaking.
The fix:
idfield202 Acceptedwith no response body for notifications2. Pre-commit Hook for Automatic Formatting
Added
.githooks/pre-committhat automatically formats staged C++ files with clang-format before commit.To enable:
git config core.hooksPath .githooksThis prevents formatting issues from reaching CI.
Test Plan