fix: silently ignore JSON-RPC notifications per spec#1
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The MCP protocol sends `notifications/initialized` after the initialize handshake. Per JSON-RPC 2.0, notifications have no `id` field and must not receive a response. Previously, the server returned a -32601 "Method not found" error for any unrecognized method, including notifications. This caused MCP clients like Forge to interpret the error response as a connection failure, preventing tools/list from succeeding. The fix checks for `request_id is None` (indicating a notification) and silently skips it via `continue`, matching the JSON-RPC 2.0 spec: "The Server MUST NOT reply to a Notification." Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
id) instead of returning a-32601 Method not founderrorProblem
The MCP protocol sends
notifications/initializedafter theinitializehandshake. Per JSON-RPC 2.0 spec, notifications have noidfield and must not receive a response.The server was returning an error response for these notifications:
{"jsonrpc": "2.0", "id": null, "error": {"code": -32601, "message": "Method not found: notifications/initialized"}}This caused MCP clients (e.g., Forge) to interpret the error as a connection failure, preventing
tools/listfrom succeeding.Fix
Check for
request_id is Nonebefore dispatching, andcontinueto skip notifications silently. This matches the JSON-RPC 2.0 spec: "The Server MUST NOT reply to a Notification."Test plan
notifications/initializedis silently ignored (no error response)tools/listreturns all 7 tools successfully after notificationidstill work as expected